Talk:Long-term effects of cannabis/Archive 1

Disputes itself
It seems like this article was written by a person who disapproves of the use of cannabis, and was then edited by a person who actively uses cannabis. Take the first paragraph from pregnancy, for example; it's basically "This is bad. But we're lying, it's everything else that's bad." This article needs to be cleaned up to have a scientific point of view, and not be written by someone who likes or opposes the drug itself. —Preceding unsigned comment added by 76.99.161.251 (talk) 01:08, 25 April 2011 (UTC)
 * The reason it disputes itself is that it cites invalid studies that aren't actually about cannabis, but about cannabis AND other drugs, which biases the results as they realistically are not related. That's bad enough solely on the bases that this is not an article about drugs in general, but only about cannabis.  Consider removing lines that cite studies which group cannabis with other drugs, and replace them with cited information about studies which separate cannabis from other drugs to compare and contrast them.  A good example would be the infant mortality rate study, which compares cannabis, cocaine, opiate, and a drug-free control as entirely separate groups; (pick a source: http://www.google.com/search?q=infant+mortality+cannabis).
 * To make matters worse, the whole article is completely disorganized. Consider separating the article into sections titled, "Risks" and "Benefits," or clearly separating each existing section into subsections by grouping the information that suggests risk and benefit.  Claims that are disputed can coexist in these formats by mentioning the study which disputes it, then going into detail about it in the opposing section.  This should allow readers to fully understand the research that has been done on the subject.  I urge writers to give details about a study's methodology to allow readers to draw their own conclusions about it's validity, especially when contrasting with one that disputes it; this is not an opinion forum.
 * 72.59.101.135 (talk) 11:30, 16 July 2011 (UTC)

Lead section added
So I wrote and added a lead for the article. I think it's a pretty fair summary - in pretty much every section, pretty much every allegation made by one side is contested by another, so I basically just said that science is strongly divided on this subject, and very little consensus exists, with a couple of examples from the article. Feel free to adjust. Peace! The Disco King (talk) 00:02, 9 July 2010 (UTC)


 * Looks good to me. Well done. Freikorp (talk) 03:41, 9 July 2010 (UTC)

You should consider writing about the possible link between cannabis smoking, and emphysema and secondary pneumothorax.


 * http://www.ncbi.nlm.nih.gov/pubmed/18657985
 * http://www.ncbi.nlm.nih.gov/pubmed/18197922
 * http://www.ncbi.nlm.nih.gov/pubmed/17931876
 * http://www.ncbi.nlm.nih.gov/pubmed/16574961 —Preceding unsigned comment added by Erik Neves (talk • contribs) 06:04, 5 August 2010 (UTC)

"Reduced Brain Size" Duplicate removed
The study that concluded that heavy use of cannabis reduces brain size was cited twice. I deleted one of the paragraphs, then I added some of its info to the second paragraph about it. It's a terribly flawed study to begin with, considering how there were hardly any participants, as well as how nothing they found could have possibly proved their conclusion given how no actual shrinking of the brain was observed. I think it should be taken out altogether, but I'll leave that decision to someone with more experience. It's bad enough that it was mentioned once, but to see it twice in this article really smacks of a desire to misinform to further a hidden agenda. I'm also wondering how all these articles appeared practically overnight about how addictive it is and how cannabis use is a disease that needs to be treated. Dkrg (talk) 04:23, 17 May 2010 (UTC)


 * I appreciate you explaining your actions here on the talk page, but the fact remains you removed two references from reliable medical sources. Shortening a section is one thing, but you are going to need a better reason than "doubting" the published journal article from a university to remove it entirely. Freikorp (talk)

Thanks for pointing that out. I definitely should've looked through the sources I removed more carefully. But I didn't remove them simply because I "doubted" them. There was a third source for the exact same study which I left in, and I thought it was a safe assumption that the information was the same for all of them. Isn't it better not to clog up the references section with multiple sources that all say the same thing? I'll admit I might've made a mistake; but again, I certainly wasn't deleting sources simply because I didn't agree with them. Dkrg (talk) 13:46, 18 May 2010 (UTC)


 * No worries. I see your point, but generally the more references the better, as online links are subject to link rot. Also the more reliable references you can find from different sources the more verified/reliable the information is deemed to be. Freikorp (talk) 14:08, 18 May 2010 (UTC)

Wait a moment! There is so much political controversy on this subject, that people are even paid to publish papers on the topic. Please go about this the scientific way, and have several confirmations on a paper, before approving it as a valid source. Anyone can become a PhD today - far from all are very good PhD's. I'm doing research on this plant, as a neuro-cognitve psychologist - and I do not agree that the use of Marijuana reduce brain size. I do not agree, that it lead to mental diseases and there is NO evidence to those claims. It is simply a political spin-off. Be very cautious around subjects that has political interest. You need to dig through a lot of bullshit before you get to the correct facts. 91.117.218.140 (talk) 09:25, 5 March 2011 (UTC)

Written by NIDA?
Would it even be worth my time to pull up conflicting studies, this article is not neutral in any regard...A better article would be "We would love to really know the long term effects of marijuana use, but unfortunately the scientific community has not had access to the plant for testing. " Also, x/150 is not a great sample margin at all, just seems like this could all be quoted better. —Preceding unsigned comment added by 68.192.37.8 (talk) 06:19, 14 June 2010 (UTC)
 * Possibly. The propaganda machine is in full swing this year due to all the new activism and possible legalization in CA. Yonskii (talk) 19:40, 23 June 2010 (UTC)
 * This article is very biased. For example take the sections on withdrawal and physical dependence. Note how the author talks about how "people used to think this", "people used to think that" (without citing anyone) then cites a load of articles that frankly don't correspond with the prevailing scientific opinion. I sense NIDA is at work here. I'd encourage anyone here to check IPs and try and track these people down. 188.220.169.56 (talk) 12:35, 4 July 2010 (UTC)

Unfair Comparison, Should Be Edited or Removed!
Jadedspider (talk) 08:12, 28 December 2010 (UTC) I wanted to point something out in this Wikipedia article about the long-term effects of cannabis. In the section covering the addictiveness of cannabis it makes general comparisons to other illicit drugs in the chart that are much more harmful in other ways both physiological and especially psychological (LSD, psilocybin). I believe this comparison is also misleading, comparing cannabis to LSD and psilocybin in this area, where it is shown to be just as similar to caffeine in addictiveness. Maybe if caffeine could be included in the comparison it would be more fair and correct, as well as give the general reader a more recognizable understanding of its addictive potential.

This is what is written-

"Despite cannabis being the most widely used illicit drug in the Western world,[19] controlled trials for cannabis use disorder have only been reported in literature in the last 15 years. Research has shown a substantial percentage of cannabis users develop cannabis-related problems, including dependency.[20][21] Overall, the addiction potential for cannabis is significantly less than that for tobacco, alcohol, cocaine or heroin, but slightly higher than that for psilocybin, mescaline, or LSD.[22][23]" (Wikipedia "Long-term effects of cannabis")

Jadedspider (talk) 08:12, 28 December 2010 (UTC)

The study in question did not include caffeine. It compared recreational drugs both legal and illegal. Same reason you dont see paracetamol up there is why you dont see caffeine -anon — Preceding unsigned comment added by 118.139.17.230 (talk) 10:20, 29 August 2011 (UTC)

Should this article even exist?
Since this article is about the fact that things are inconclusive as to the long-term effects, what benefit is made by putting up all the theories that are being tested rather than waiting for the facts to come through and record those? The cannabis drug use article should be edited to include a footnote about the long term effects being unknown and this article should be removed until we actually know what the long-term effects are. (-ferocioustick 18/09/2011 02:56 CST) — Preceding unsigned comment added by Ferocioustick (talk • contribs) 07:57, 18 September 2011 (UTC)
 * The lead says that.--Metallurgist (talk) 04:52, 10 October 2011 (UTC)

Cannabis and pregnancy
My sincere apologies for not having the relevant scientific reports to hand but in the section here about cannabis use during pregnancy, the article implies that caffeine has a negative effect on the unborn child. This was recently proven inaccurate as only vast amounts of caffeine would produce this sort of potential fetal deformity. By keeping this section in, unmoderated and uncited, this likens a caffeine drink such as a cup of tea to a joint, an unfair comparison to make. Not that Wikipedia is responsible and I'm sure it was not the original authors' intention however, my experience leads me to believe that all Wikipedia articles have an assumed authority based on the fact that specialists and experts can edit away bad data. I hope someone here can find the articles (I'm not from a science background but do enjoy copious amounts of tea, though not cannabis nor babies) to correct the section. — Preceding unsigned comment added by 77.101.64.152 (talk) 21:19, 20 February 2012 (UTC)

Omission of Cancer-related Evidence
I haven't had the time to go back into the history to see whether these were once here and later removed, but there is now a substantial body of peer-reviewed research in major medical journals that finds not just lack of harm but actual positive effects in cannabis consumption, and this article currently omits discussion of the evidence altogether. This article does not seem to me to have the proper NPOV, which would present all the evidence, whether it is "good" or bad." The omission of cancer-protective studies is especially troubling given the number of places where the current article suggests that pot causes cancer. Examples of peer-reviewed studies in leading medical journals (which a Wikipedia article should be mentioning, rather than arguing with or dismissing, as I understand NPOV guidelines) include:


 * "A Population-Based Case-Control Study of Marijuana Use and Head and Neck Squamous Cell Carcinoma": http://cancerpreventionresearch.aacrjournals.org/content/early/2009/07/28/1940-6207.CAPR-09-0048.short, which concludes that "Our study suggests that moderate marijuana use is associated with reduced risk of HNSCC."
 * "Cannabinoids, endocannabinoids, and cancer": http://www.ncbi.nlm.nih.gov/pubmed/22038019, which concludes that "the endocannabinoid system is a promising new target for the development of novel chemotherapeutics to treat cancer"
 * "Delta9-Tetrahydrocannabinol inhibits epithelial growth factor-induced lung cancer cell migration in vitro as well as its growth and metastasis in vivo." http://www.ncbi.nlm.nih.gov/pubmed?term=Preet%20A%202007, concluding that "Tumor samples from THC-treated animals revealed antiproliferative and antiangiogenic effects of THC. Our study suggests that cannabinoids like THC should be explored as novel therapeutic molecules in controlling the growth and metastasis of certain lung cancers."

there is other, IMO less robust, research suggesting a causal link between cannabinoids and cancer, often in vitro as opposed to in vivo (most of the above studies are in vivo) not cited here.

Currently this article gives a very different impression of the overall science on long-term marijuana use, especially its impact on cancer, than does searching for "Cannabis" in PubMed. I would think the impression should be close to identical. Wichitalineman (talk) 19:17, 8 June 2012 (UTC)

Rats are not people
Gateway drug hypothesis study does not take into account rats and people are not even close. Many factors take into account whether a teenager who smoked cannibis will or will not eventually lead to more harmful drugs. Rats do not have the choices because they are in a cage with limited interaction and nevermind they are freakn rats. This study is pointless and this section should either find a study that does link the Gateway hypothesis or remove it competely. 18:57, 29 June 2012 (UTC) — Preceding unsigned comment added by 24.123.147.3 (talk)

New study
I thought this was worth adding. It specifically deals with marijuana and intelligence, attention and memory.

http://www.sciencedaily.com/releases/2012/08/120827152039.htm

205.217.239.56 (talk) 05:29, 2 September 2012 (UTC)

This small study with better methodology shows no effect. They actually tested for marijuana usage whereas in the New Zealand study abstinence was self reported.

http://www.newscientist.com/article/dn2140-marijuana-does-not-dent-iq-permanently.html "Current and former marijuana use: preliminary findings of a longitudinal study of effects on IQ in young adults" http://www.cmaj.ca/content/166/7/887.full?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=cannabis&searchid=1025853946146_44&stored_search=&FIRSTINDEX=0&journalcode=cmaj

"Long-term" Definition
Would it be possible to have some kind of definition as to what "long-term" is. Are we talking about a month/year/decades of smoking daily for instance? Perhaps there should be some discussion of this on the page. — Preceding unsigned comment added by 85.211.12.149 (talk) 00:46, 4 September 2012 (UTC)

I would say any effects that last after the chemical is no longer present in the body in significant amounts and any rebound effects are over is a long-term effect. Exercisephys (talk) 21:38, 15 May 2013 (UTC)

Removed for lack of reference
There was no reference given for this material.  petrarchan47  t  c   20:39, 29 December 2012 (UTC)
 * "The term cannabis-associated respiratory disease can refer to neoplastic (tumor-forming) processes or structural damage in the lung. Note, Cannabinoids have been shown in vitro to have antineoplastin activity, however, inhaling vapors of any vegetative matter, heated to near its flash point, regularly, can be shown to cause malignancies, as carcinogens are found in high concentrations specifically in the particulate residues, but also the gaseous products of oxidative decomposition."

Nor this   petrarchan47  t  c   20:49, 29 December 2012 (UTC)
 * "Research has shown a substantial percentage of cannabis users develop cannabis-related problems, including dependency"

Section removed for lack of secondary source
This section needs a secondary source, otherwise this is a set of primary sources strung together to make a claim that may not be made elsewhere, and may not be an accurate assessment of the studies cited. This was the only reference from the section that I was able to access.  petrarchan47  t  c   08:37, 31 December 2012 (UTC)

"Smoking cessation" ''Cannabis is the most widely used illegal drug in the Western world. There is plenty of documented evidence to suggest a need for users to find ways to assist them to stop using cannabis and the demand for treatment for cannabis dependency is increasing internationally. There are a number of ways to quit cannabis and increasing evidence-based treatments for cannabis users wishing to change the patterns of their use. This article deals with the different interventions to assist in the cessation of cannabis use.''

Recent change per WP:MEDRS
This change was made per the following line from WP:MEDRS ".... edits that rely on primary sources should only describe the conclusions of the source, and should describe these findings clearly so the edit can be checked by editors with no specialist knowledge".  petrarchan47  t  c   23:16, 13 January 2013 (UTC)

Total Page Revision
This page has become a matted net of cruft and I'm trying to comb it out. It's definitely a little bit of a rough way of doing things but it needs desperately to be done. I'm essentially copy-editing the whole thing: changing what formatting needs to be changed, checking sources for validity and finding new ones where necessary, keeping the analysis fair and conservative, and above all trying to develop a little coherence. Please message me if you have any concerns before reverting anything, as most of my edits are dependent on one another at this point. Thanks. Exercisephys (talk) 21:43, 15 May 2013 (UTC)

A note on sourcing
Per WP:SCHOLARSHIP, "Articles should rely on secondary sources whenever possible. For example, a review article, monograph, or textbook is better than a primary research paper. When relying on primary sources, extreme caution is advised: Wikipedians should never interpret the content of primary sources for themselves. See WP:OR"   petrarchan47  t  c   05:42, 19 May 2013 (UTC)
 * Don't you feel that this has severe limitations, especially with topics related to drugs? News sources in particular tend to embellish statistics and inject POV, while providing a seriously insufficient summary of the study. Exercisephys (talk) 15:53, 19 May 2013 (UTC)
 * It's probably not a perfect scenerio, but these articles are written for the layperson, per WP:TECHNICAL, as are news sources. If good WP:RS show a source to be misleading, it can be removed or new information can be added.  petrarchan47  t  c   00:12, 20 May 2013 (UTC)

Merge
''In a study of ten smokers with mild respiratory issues Hii et al. found evidence of lung disease in the form of severe bullae (fluid-filled, thin-walled blisters) of different shapes and sizes. Despite such lung disease, the patients' chest x-rays were normal and lung function was only mildly reduced in nearly half of the patients. The cannabis-smoking patient group was, on average, 41 years old—considerably younger than previously research tobacco-smoking patients with lung disease, who had an average age of between 62–67 years. The researchers conclude that the younger age of lung disease and poorer lung function may be due to different smoking patterns demonstrated in cannabis smokers,[Hii, S.W., Tam, J.D.C., Thompson, B.R. & Naughton, M.T. (2008). Bullous lung disease due to marijuana. Respirology 13, 122-127 ] who have been found to inhale larger amounts of smoke, which is held in the lungs for longer periods of time.''source

Just finished the merge of content from Cannabis-associated respiratory disease. This above is the only sourced claim that was not merged here. A study of ten people does not warrant mention, imo, but wanted to leave it here in case others disagreed.  petrarchan47  t  c   06:33, 27 May 2013 (UTC)

Immune system?
There is no mention in this article about THC and the immune system. Since immune cells, like the brain, have cannabinoid receptors, there should be an effect. 2602:306:CD65:6650:E198:7324:9AFC:FB49 (talk) 19:23, 1 August 2013 (UTC)

Conflicting science
The article in the intro says that the science is contradictory, but it cites two studies that studied completely different diseases. You can't say that the science is contradictory and then show one article that says marijuana may increase the risk of heart disease and then another that says it found no effect on schizophrenia. This isn't contradictory!!! — Preceding unsigned comment added by 98.180.39.231 (talk) 18:08, 6 September 2013 (UTC)

WP:EL
I'm not sure how any of these meet WP:EL: Best. Biosthmors (talk) pls notify me (i.e. ) while signing a reply, thx 18:38, 21 September 2013 (UTC)
 * Cannabis Use and Psychosis from National Drug and Alcohol Research Centre, Australia
 * Provision of Marijuana and Other Compounds For Scientific Research recommendations of The National Institute on Drug Abuse National Advisory Council
 * The Brain's Own Marijuana Scientific American (December 2004)
 * Ramström, J. (2003), Adverse Health Consequences of Cannabis Use, A Survey of Scientific Studies Published up to and including the Autumn of 2003, National institute of public health, Sweden, Stockholm.
 * Hall, W., Solowij, N., Lemon, J., The Health and Psychological Consequences of Cannabis Use. Canberra: Australian Government Publishing Service; 1994.
 * World Health Organisation, PROGRAMME ON SUBSTANCE ABUSE, Cannabis: a health perspective and research agenda (1997).
 * The National Cannabis Prevention and Information Centre (Australia)
 * EU Research paper on the potency of Cannabis (2004)


 * None seem on topic about the long term effects of cannabis♫ SqueakBox talk contribs 19:09, 21 September 2013 (UTC)

Merge discussion, Cannabis (drug)
Cannabis_(drug) is a poor summary of this article, out-of-sync, and needs to be shortened, synced, and rewritten to use summary style, with any salvageable content moved here. Sandy Georgia (Talk) 22:36, 1 December 2013 (UTC)

Merge proposal, cannabis in pregnancy
The cannabis in pregnancy article should be merged here. Sandy Georgia (Talk) 16:03, 1 December 2013 (UTC)


 * Support. Merge to the pregnancy section here (which itself needs big cleanup). Alexbrn talk 16:06, 1 December 2013 (UTC)


 * Support. Should never have been made into a separate article♫ SqueakBox talk contribs 22:43, 1 December 2013 (UTC)


 * Oppose. I don't see any reason why the article should be merged other than that its not presently well developed enough to stand alone. I can understand though why one would want to temporarily merge it, but there is no reason that I can think of why a perfectly good article couldn't be made out of the effects of cannabis on pregnancy. Better to improve cannabis in pregnancy rather then merging it in my opinion.Chhe (talk) 02:00, 2 December 2013 (UTC)
 * Are you aware of other sources that meet WP:MEDRS that can be used to develop it further? Sandy Georgia (Talk) 03:02, 2 December 2013 (UTC)
 * Oh my, a PubMed search on reviews only for pregnancy cannabis reveals there are scores of recent secondary reviews that can probably be used to develop cannabis in pregnancy. I will list them at Talk:Cannabis in pregnancy, and then we can better determine if content should be merged.  Sandy Georgia  (Talk) 03:09, 2 December 2013 (UTC)
 * and, could you have a look at the sources I listed at Talk:Cannabis in pregnancy and opine whether there is sufficient content from those articles that warrant development in that article, or if those new sources say nothing more than what we already say? Sandy Georgia  (Talk) 03:31, 2 December 2013 (UTC)
 * I'd assumed we would re-build after the current round of emergency removal of bad material; whether there's enough here for a standalone article, or just a more substantial section in a parent article, I'm not sure. Alexbrn talk 08:52, 2 December 2013 (UTC)


 * support-- there appears to be not much left on Cannabis in pregnancy once primary sources are removed. Whatever is left should be merged somewhere, I'm guessing the main cannabis page. I've not looked at any other articles yet. Lesion  ( talk ) 06:53, 3 December 2013 (UTC)
 * Nvr mind, I realized article has been reworked since I looked at it before. Lesion  ( talk ) 06:58, 3 December 2013 (UTC)

I've worked in briefly what I can from those that have free full text available. There is a wealth of information and I can't begin to add all of it, so I have basically only added the conclusions from the reviews. I think an article can be developed there, so unless anyone objects, I will remove the merge proposal. Sandy Georgia (Talk) 16:52, 2 December 2013 (UTC)
 * OK, I'm removing the merge proposal, since I've incorporated a number of new sources, and have barely scratched the surface of the content that can be gleaned from those sources. Sandy Georgia  (Talk) 07:08, 3 December 2013 (UTC)

I suspect this article has a few contributions from stoners
I was reading the section on the effects on the lungs, and the first paragraph in particular seems really meandering, a lot of detail but no real coherence. And for the length of the section it'd be nice to learn something new.

Maybe I'd look for some research and contribute myself but I'm high and also lazy.

Kickflipthecat (talk) 07:17, 27 September 2013 (UTC)


 * These sections have been chopped, pasted, and copy-edited sentence-by-sentence a handful times. I agree that someone should audit articles like this to be more coherent and linear, but someone needs to make a significant time commitment for that to happen. Exercisephys (talk) 16:35, 27 September 2013 (UTC)


 * Not only is it impossible to tell whether some editors use cannabis but it makes not the slightest difference whether they do or not, we simply respect the privacy of all editors and base ourselves on the edits and not on what we think of the editors♫ SqueakBox talk contribs 20:26, 3 December 2013 (UTC)

Affect on White Matter in the Brain
I thought this (or similar information from another source) could possibly be of interest for this article, since the section on intelligence seems to be very one-sided in this article (if anything, a quick cruise around Google makes it apparent that most sources seem to agree that it does impair intelligence long-term). http://www.medicaldaily.com/marijuana-use-causes-brain-damage-confirmed-241869 — Preceding unsigned comment added by 172.242.49.60 (talk) 19:30, 3 December 2013 (UTC)
 * Thanks, 172, but please review WP:RECENTISM and WP:NOT (news) along with our medical sourcing guidelines. Medical content is ideally sourced to secondary reviews of primary studies, and rarely to press reports.  We do have numerous secondary reviews in this realm, but the article is currently being developed to cover what reliable medical sources say.  Sandy Georgia  (Talk) 19:34, 3 December 2013 (UTC)
 * One limitation of that study was that users were still high. The cannabis smoking group smoked an average of 5 joints per day. Median self-reported abstinence was only 15 hours, which is not nearly enough to clear THC or it's metabolites for such excessive smokers. — Preceding unsigned comment added by Psyden (talk • contribs) 22:16, 3 December 2013 (UTC)

Respiratory effects
Hello everybody. First of all, I apologize for my english in advance: I'm not a mothertongue so I might make mistakes. I noticed this page changed significantly in the last month, and that many sources have been removed (not without a reason, from what i read in this discussion). However, it's not clear to me why the "respiratory effects" section has been changed. In particular, two major sources (http://www.webmd.com/lung-cancer/news/20060523/pot-smoking-not-linked-to-lung-cancer http://healthland.time.com/2012/01/10/study-smoking-marijuana-not-linked-with-lung-damage/) about important studies suggesting no correlation between marijuana use and lung disease/cancer have been removed and the "literature review by Gordon and colleagues" has been added. Moreover, the study by the British Lung Foundation has been heavily criticized by many (http://www.bbc.co.uk/news/health-18283689 http://profdavidnutt.wordpress.com/2012/06/11/smoke-without-fire-scaremongering-by-the-british-lung-foundation-over-cannabis-vs-tobacco/); it is not up to us to say whether the BLF is right or wrong, but I think it should be specified that the study is object of a hot debate. MarkyRamone92 (talk) 11:21, 10 December 2013 (UTC)
 * I agree there has been cherry picking in what has been removed, and added. We are noting this same thing with regard to medical use at Medical Cannabis. There doesn't seem to be a way to argue with a whole team of folks with similar views however, but good luck.  petrarchan47  t  c   17:55, 11 December 2013 (UTC)

Animal studies
, I wanted to call to your attention your correct removal of this edit, by but for the wrong reason :)   is a secondary review; the problem is that it's from 1992.  WP:MEDRS tells us to avoid (over-emphasizing) single animal studies, and to recognize that animal studies might not translate to humans, but recent reviews that do discuss animal studies in context are generally acceptable, if not over-emphasized.  This instance was correctly reverted, but our medical sourcing guidelines don't disallow mention of animal studies from recent reviews that place them in context.  If the conclusions of the 1992 review are relevant today, recent reviews will have covered them.  Sandy Georgia  (Talk) 13:50, 12 December 2013 (UTC)
 * Thank you for clarifying. I should have been more specific in the removal comment. I also found that review has been disputed here: Psyden (talk) 13:58, 12 December 2013 (UTC)

Sorry, I didn't see the refuting paper. , I didn't see the following results in the article either. They look topical and on their face look like they meet RS guidelines. or. They are newer with both human and mouse studies. I don't know if they've been discussed before or if they meet WP:MEDRS --DHeyward (talk) 22:14, 13 December 2013 (UTC)
 * Hi, -- no concerns, there has been a lot going on here, and I wanted to make sure Psyden and I were on the same page. Of the two you list, the first is a recent primary study on animals, and the second is a comment.  I wouldn't be comfortable using either of those, per WP:RECENTISM, WP:UNDUE, and WP:MEDRS.  Best, Sandy Georgia  (Talk) 22:24, 13 December 2013 (UTC)
 * Okay. I didn't have access to the comment paper, just abstract.  Comment author seems positive about value of medicinal marijuana so I thought it would balance the tone with both.  The human study underlying the basis for the primary mouse research is , which I didn't find in WP either as a citation (save on a user's page).  The human study has been cited 21 times in pubmed articles.    --DHeyward (talk) 22:46, 13 December 2013 (UTC)

Poor sourcing, original research
A now deleted student essay on epilepsy and cannabis, led me to have a new look at medical cannabis (which was almost exclusively cited to primary sources), which led me next here, where I find not only an overreliance on primary sources, but also blogs and a letter plus a clinical trial used to contradict a secondary reviews. Original research is generated by stringing together primary sources to draw conclusions. Please review WP:MEDRS, WP:SYNTH, WP:NOT (news). There is a good deal of cleanup needed in here-- too much for one day, or one week. Sandy Georgia (Talk) 03:54, 30 November 2013 (UTC)

Mental health section
We should be able to improve some of the references in this section. I suggest that the following two reviews may be considered as representing latest mainstream views: I think the introduction could be re-written to simply state conclusions. The issues that I feel need to be mentioned are: Any other relevant sources and issues that ought to be considered for the introduction? --RexxS (talk) 17:22, 14 December 2013 (UTC)
 * McLaren 2008 is getting a bit old - later reviews ought to be able to say something about cannabis' association with anxiety, psychosis, and depression;
 * Moore 2007 is also dated - it's used to support results about dosage and incidence of psychotic illness;
 * The BEACH citation is presently worthless, especially to support a direct quote; I've done a text search on the site (Google "cannabis smokers are more likely to suffer depression site:http://sydney.edu.au/") and I can't find the text, so it ought to go. It covers the issues of self-reporting to GPs and co-incidence of psychological conditions.
 * - "Heavy cannabis use at a young age, in association with genetic liability to psychosis and exposure to environmental stressors like childhood trauma and urban upbringing increases the risk of psychotic outcome in later life." "Cannabis acts as a component cause of psychosis, that is, it increases the risk of psychosis in people with certain genetic or environmental vulnerabilities, though by itself, it is neither a sufficient nor a necessary cause of psychosis."
 * - "Cannabis is not a safe drug. Depending on how often someone uses, the age of onset, the potency of the cannabis that is used and someone’s individual sensitivity, the recreational use of cannabis may cause permanent psychological disorders." "Studies examining the protective effects of CBD have shown that CBD can counteract the negative effects of THC."
 * Increased risk of psychosis related to dosage, frequency of use, age at initial exposure and other factors;
 * Cannabis as a component cause;
 * The relationship between THC and CBD in the risk of psychological disorders;
 * There are quite a few listed at User:SandyGeorgia/Cannabis sources . With all those sources, you might see why I've been reluctant to begin work on that section :)  Sandy Georgia  (Talk) 17:28, 14 December 2013 (UTC)
 * Thanks Sandy, that's quite a lot to take in. I'd read a couple of those before and some are very specific to particular topics, so will be useful for the subsections. I think I'd generally prefer the 2013 reviews - particularly as coming from Indian and Dutch authors - to any of the 2010 ones. I get the impression that evidence has firmed up the mainstream view over the last few years, but the interesting relationship between THC and CBD is only recently receiving attention. I'm going to try a more concise introduction and see if it gets consensus. Cheers --RexxS (talk) 18:04, 14 December 2013 (UTC)

, we also have this: Sandy Georgia (Talk) 17:28, 18 December 2013 (UTC)

Revert

 * You have completely destroyed this article SandyGeorge. It is pretty obvious you are sharply anti-marijuana. — Preceding unsigned comment added by Psyden (talk • contribs) 23:53, 2 December 2013 (UTC)
 * No I haven't; I'm still working. Removing original research, synthesis, and text duplicated across multiple articles.  Since there are good sources available, I recommend using them.  Good sourcing has nothing to do with being pro- or anti-anything, except that is, pro-good sourcing.  Sandy Georgia  (Talk) 23:56, 2 December 2013 (UTC)
 * Previously the article had evidence for and against each claim. Now, in the name of removing primary sources, the article mainly lists detrimental effects of marijuana. Leave in the primary sources unless you can find a secondary source making the same claim. Don't eliminate the claim entirely. For example, you removed the reference to one of the largest peer-reviewed studies of it's kind in regard to lung, oral, laryngeal, pharyngeal, and esophageal cancer. This study, done by a leading expert in the field, concluded that "the association of these cancers with marijuana, even long-term or heavy use, is not strong and may be below practically detectable limits" when adjusting for confounders including tobacco and alcohol use Tashkin study. There is nothing complicated about this conclusion. Any "lay" person can understand it. It is not really open to interpretation. You removed that study but leave in the ridiculous claim by the BLF that implies marijuana is 20 times more carcinogenic than tobacco Cannabis 20 times more carcinogenic than tobacco? . While the effort to clean up the page is appreciated, it does not seem you are approaching this in a balanced way. Psyden (talk) 14:46, 3 December 2013 (UTC)
 * Primary sources, whether for or against, should not be used, per WP:MEDRS. It matters little about how big the primary source is, Wikipedia's medical content should be based on reviews, ideally systematic reviews, and mainstream textbooks. Primary sources should particularly not be used to contradict secondary sources. Position statements from major, mainstream organizations are also sometimes useful. Wikipedia's medical content should reflect the mainstream view, even if some people feel that the mainstream view is incorrect. Lesion  ( talk ) 15:13, 3 December 2013 (UTC)
 * Well, a significant scholarly view that contradicts the scholarly mainstream should be represented here, too - but such a view must be supported by the types of sources Lesion mentions, as outlined in Identifying reliable sources (medicine), and given about the same relative emphasis it is given in scholarly overviews. --Anthonyhcole (talk · contribs · email) 15:25, 3 December 2013 (UTC)
 * Re. same relative emphasis, please see WP:UNDUE. Lesion  ( talk ) 15:35, 3 December 2013 (UTC)
 * Psyden, what was there previously was synthesis from primary sources. That is not acceptable under any circumstances, and although I'm working as hard and as fast as I can to replace primary sources with secondary, it is not possible for one editor to clean up a mess this big in a day or two.  I have included secondary sources that can be used for expansion, and you are welcome to find more or to expand text further than I have based on secondary sources.  Yes, my work is somewhat sporadic as I'm proceeding according to the sources as I locate and read them.   Help is appreciated; at this point, there is no rhyme or reason to what has been replaced and what has not, other than which sources I have located so far.  Sandy Georgia  (Talk) 17:10, 3 December 2013 (UTC)

, please explain your removal of maintenance tags, and a revert that removed text cited to WP:MEDRS-compliant secondary sources to reinstate text cited to primary sources and containing original research and synthesis. This is the version you reverted from, which had replaced about half of the primary sources with secondary reviews, and this is the version you reinstated, with tag removal and with a personal attack in edit summary. Are you familiar with Wikipedia's medical sourcing guidelines? Sandy Georgia (Talk) 00:19, 3 December 2013 (UTC)
 * Agree secondary sources are required per WP:RS and WP:MEDRS. Please do not restore primary sources as this is against consensus. Doc James  (talk · contribs · email) (if I write on your page reply on mine) 00:39, 3 December 2013 (UTC)
 * Psyden, there are ample what one might call pro cannabis reliable secondary sources out there, relying on primary sources as a way of making the article seem neutral is absolutely NOT the way to go, I dont believe that what Sandy is trying to achieve is going to make the article anti-cannabis but it may be down to other editors to add good secondary sources for material that is kind to cannabis. Its not like pro-cannabis is fringe and anti-cannabis is mainstream, perhaps ten years ago but not in 2013. ♫ SqueakBox talk contribs 01:00, 3 December 2013 (UTC)
 * Agree some secondary support certain indications and others are more hesitant. The minimum is that all use high quality secondary sources from the last 5 years or so. Doc James  (talk · contribs · email) (if I write on your page reply on mine) 01:08, 3 December 2013 (UTC)
 * Agree with SqueakBox, and I am trying to rebuild as much as I can, using what secondary sources I can access, but I will be disinclined to continue trying to build good content if my efforts will just be reverted. There are plenty of good sources available-- it isn't a matter of pro or con-- it's more a matter of getting this suite of articles to a place where they can be more easily cited and maintained, by using summary style correctly so that text is in one article rather than four.  Right now, there's a lot of poorly sourced text, that is duplicated across sometimes five or six articles that are not in sync.  It will take some time to correct all of this, but it is doable, and I don't believe the text cited to secondary sources at medical cannabis is coming out either "pro" or "con"-- it's coming out factual.  I will continue trying to work if the work won't be reverted-- in many cases, this means paying or traveling to get access to full journal articles. Medical cannabis has now been fairly well cited and organized, and it would be helpful if folks would fill in the missing citations there so all tags can be removed.  It's got a good start now.  Sandy Georgia  (Talk) 01:27, 3 December 2013 (UTC)

-Now I should pay 40$ to read Gordon's literature review? (Gordon AJ, Conley JW, Gordon JM (December 2013). "Medical consequences of marijuana use: a review of current literature". Curr Psychiatry Rep 15 (12): 41). Thank you SandyGeorge to base large parts of this article on literature which isn't freely available. -I also find it kind of presumptuous to delete large parts and then come up with the excuse you don't have time to source the article properly nor to rewrite the passages deleted. -I vote revert!! --Mikeschaerer (talk) 08:56, 20 December 2013 (UTC)
 * Deleting poor content improves Wikipedia. For Gordon, an alternative to paying is using a library. The sources we use do not need to be available free-of-charge. Alexbrn talk 10:04, 20 December 2013 (UTC)
 * Hi, Mikeschaerer, it's nice of you to drop in to offer an opinion for your second edit to Wikipedia. Please see WP:PAYWALL and WP:CONSENSUS.  Sandy Georgia  (Talk) 15:42, 20 December 2013 (UTC)

Cognitive decline
I've removed this section as it has no more than peripheral relevance to "Long-term effects of cannabis":

Cognitive decline
Cannabinoids are strong antioxidants and therefore defend cells from ß-amyloid, the peptide that causes Alzheimer's disease. Some studies have found that cannabis has no effect on ageing-related cognitive decline while others suggest that it slows cognitive decline through its antioxidant effect. The cannabinoids present in cannabis lessen cell damage and death from ischemia, likely due to their antioxidant properties.

I think it may have some use in the Medical cannabis article, but while trying to find sources for the long-term effects of cannabis on dementia, I found more recent sources that would help to put the above paragraph into better perspective. I suggest something like the following would be an improvement:

Cannabinoids are antioxidants and CBD has anti-inflammatory and neuroprotective properties.

A 2007 review suggested that THC may be effective in preventing the production of ß-amyloid, the peptide implicated in Alzheimer's disease, and that CBD may prevent some of its neurotoxic effects.

However a 2009 Cochrane review was unable to find evidence that cannabinoids are clinically effective in the treatment of dementia and suggested further randomised controlled trials should be conducted to investigate.

The use of CBD and cannabis derivatives such as nabiximols has also been suggested for use in treating or protecting against ischemic stroke, and Huntington's disease, as well as for slowing down brain ageing and ameliorating symptoms of neurodegenerative disorders.

If nobody has a chance to make use of it by the time I've finished cleaning up here, I'll try to incorporate it into Medical cannabis myself. --RexxS (talk) 21:26, 21 December 2013 (UTC)

Long term effects of cocaine & cannabis?
Why is this in the article? Pregnancy section: "evidence that prenatal exposure to marijuana and cocaine has serious effects on the developing brain and is associated with "deficits in language, attention, areas of cognitive performance, and delinquent behavior in adolescence".

What does this tell anyone about cannabis? Thanks in advance,   petrarchan47  t  c   01:52, 21 December 2013 (UTC)
 * Removed cocaine. Sandy Georgia  (Talk) 02:19, 21 December 2013 (UTC)
 * Irrelevant unless the study you're quoting removed cocaine too. Why, in other words, is this study being used to speak about cannabis? Isn't cocaine a confounding factor? If there are no studies we can reference that don't have other drugs or alcohol mixed in, we should state that and refrain from making claims about cannabis alone when the study quoted does not.  petrarchan47  t  c   04:40, 22 December 2013 (UTC)
 * Agreed. 15:31, 22 December 2013 (UTC) Psyden (talk) 15:32, 22 December 2013 (UTC)
 * The review cited is
 * which analyses 25 different studies, several of which quite specifically control for individual substances (alcohol, tobacco, marijuana, cocaine). In the opening paragraph Irna highlights Day, Leech & Goldschmidt 2011, a study specifically addressing the association between prenatal marijuana exposure and delinquency. Irna is quite clear in her discussion of relevant factors that differences are apparent in the degree of effects of different substances, so I cannot see grounds for an objection. This is a recent peer-reviewed systematic review published in a respected scholarly journal and it's not our place to argue with its findings. --RexxS (talk) 17:34, 22 December 2013 (UTC)
 * Yes, the author sorts the various substances and studies, there are two large tables of the different studies, substances and results, and I left (abbreviated) excerpts at the relevant article for this discussion, Talk:Cannabis in pregnancy. (For some weird reason, this is being discussed on three talk pages-- see Summary style-- the text is summarized from the main article).  Sandy Georgia  (Talk) 20:04, 22 December 2013 (UTC)
 * Yes, the author sorts the various substances and studies, there are two large tables of the different studies, substances and results, and I left (abbreviated) excerpts at the relevant article for this discussion, Talk:Cannabis in pregnancy. (For some weird reason, this is being discussed on three talk pages-- see Summary style-- the text is summarized from the main article).  Sandy Georgia  (Talk) 20:04, 22 December 2013 (UTC)

Attribution of sources
Our policy on attribution (WP:ASSERT} states:


 * "When a statement is a fact (a piece of information about which there is no serious dispute) it should be asserted without prefixing it with "(Source) says that ...", and when a statement is an opinion (a matter which is subject to dispute) it should be attributed to the source that offered the opinion using inline-text attribution. In-text attribution to sources should be used where reliable sources disagree, not where editors disagree.

So please let's not start applying attribution to sources that are not contradicted by other equally reliable sources - it simply looks like an attempt to imply that significant disagreement exists where none does.

A 2013 review of data by Chadwick et al found "the association between early cannabis exposure and vulnerability to schizophrenia is related to individual genetics". No data exists to support a causal relationship. The researchers stated, "Whether the early onset of cannabis use relates to preexisting pathology that is then exacerbated by the drug is still debated."

A meta-analysis of cannabis use on neurocognition in schizophrenia found "superior performance in cannabis-using patients" compared with those with schizophrenia who did not use cannabis.

If we want to say that the association between early cannabis exposure and vulnerability to schizophrenia is related to individual genetics, then we do so - although the previous paragraph already makes that point (I thought) and more succinctly. We don't say "no data exists" unless the source says so - to do otherwise is our own original research. Our job as editors is to neutrally summarise sources; it is poor editing to pick chunks of a review and quote them - at some point we are infringing copyright, when we are all perfectly capable of summarising.

The point that Chadwick makes about "Whether the early onset of cannabis use relates to preexisting pathology that is then exacerbated by the drug is still debated" is not specific to schizophrenia, so does not belong in this section. It either needs to be part of the introduction to the Mental health section or arguably in the Chronic psychosis section. I'd be happy to support a summary of that conclusion in either of those places.

The Rabin 2011 analysis is an important finding and I've tried to summarise the finding in the first paragraph of the section, which deals with the effects on existing schizophrenia. --RexxS (talk) 16:39, 22 December 2013 (UTC)
 * , one of the reasons I over-attributed a lot of text in these articles is that direct quotes should be attributed, and I was directly (over)quoting because I expected a lot of the material to be challenged. I agree that if text cited to recent secondary reviews is paraphrased, attribution isn't needed.  Sandy Georgia  (Talk) 20:06, 22 December 2013 (UTC)

Literature reviews
Hello everybody. I noticed that a very large portion of the article is based on the "Gordon et al. literature review", including the sentence "Cannabis use is associated with social and behavioural problems, and carries a risk to mental and physical health" in the second paragraph. Suggesting a consensus on the negative long-term effects of cannabis, it's a major statement that IMHO needs further sources, as it's the single most important sentence in the whole article. Moreover, the section about the correlation between cannabis use and cancer is based on that literature review only, and that should be discussed too, IMHO. I also suggest reading this (http://www.bisdro.uni-bremen.de/boellinger/cannabis/08-zi-mo.pdf) literature review, that comes to different conclusions. I'd like to start a discussion on these matters if possible as I didn't get any answer on my previous doubts on the "Respiratory effects" section (see above). Thank you, MarkyRamone92 (talk) 15:01, 27 December 2013 (UTC)
 * You are citing a 20-yo book, to rebut a current journal review. (Have a look at WP:MEDDATE and WP:MEDRS.)
 * Of the current 55 citations in the article, 13 of them are to Gordon (not an unusual amount considering it is among the most recent).
 * There are multiple other sources for the statement you question (see User:SandyGeorgia/Cannabis sources for a non-exhaustive sample).
 * Perchance your previous post received few comments because this suite of articles has been the subject of recruiting, and you are a new poster who has posted on no other topic.
 * Sandy Georgia (Talk) 16:42, 27 December 2013 (UTC)
 * Sandy, that is entirely unfounded. I have gone out of my way to be clear about what I was doing, and I have only one person helping me, as I've told Project Medicine, though he is not actually editing. You do not have a basis for these claims. It is shocking to see this used as justification to ignore other editors.  petrarchan47  t  c   13:12, 4 January 2014 (UTC)


 * I haven't been recruited; in fact, I've spent quite some time on wiki years ago, but not on en.wiki. I'm italian, so i used to work on it.wiki.
 * I didn't know about the sandbox, and unfortunately I don't have much time right now to check all those sources. Still, at the moment in the article the literature review is the only source for that statement, which is IMHO something that should be fixed as soon as possible.
 * I didn't say that the whole article is based on the Gordon review, because that is not true. Nevertheless, I do see that many important sections are based almost exclusively on that review, namely those about the effects on the lungs and the correlation between cannabis use and cancer.
 * As I wrote in the "respiratory issues" section of this discussion, the British Lung Foundation study has been heavily criticized. Shouldn't we mention that?
 * MarkyRamone92 (talk) 17:22, 27 December 2013 (UTC)
 * Welcome to Wikipedia, . Perhaps I can help you a little by drawing your attention to the top of this page, where it points out that "This is not a forum for general discussion of the article's subject." so discussion here should be about how we can improve the article. That means that we've agreed to follow a number of conventions in writing the content of the article. You could take the time to read WP:MEDRS for a full description of how we identify reliable sources, but a brief précis would be that we try, wherever possible, to summarise the conclusions of secondary sources that are published in respected journals in the last few years. The point of that is we expect the editorial processes and peer-review of scholarly journals to ensure that we have good information; and that systematic reviews, meta-analyses, literature reviews, etc. (i.e. secondary sources) will take into account all of the relevant primary evidence and take on the job of analysing and weighting that evidence in reaching those conclusions. A corollary of that is we don't use primary sources to rebut the conclusions of a good-quality secondary source.
 * Gordon (2013) is a literature review published in 'Current Psychiatry Reports', a Springer Verlag journal with an impact factor of 3.23, and appears in the major indexes. It's the sort of sort of source that our guidelines tell us to look for; all of this gives us confidence in the conclusions the authors reach. Now http://www.bisdro.uni-bremen.de/boellinger/cannabis/08-zi-mo.pdf doesn't seem to have been published in a scholarly journal at all - at least I can't find its title in a PubMed search, and it doesn't seem to have a date either. It does seem to have been originally published as monograph by The Lindesmith Center in New York City - described as a "social advocacy organization". So we don't have the backing of a respected journal to give the source authority. We could examine the authors' published works to establish whether they have authority in the mainstream view of the field? I can see their background ([http://medicalmarijuana.procon.org/view.source.php?sourceID=000233 for example). Unfortunately I don't see any articles they have published that are indexed in PubMed. There's a JP Morgan who is a dentist and an L Zimmer who researches melanomas, but that's about it. I could be wrong of course, but I can't see how our guidelines would recognise the source you suggest as authoritative.
 * As you bring up the question of the Respiratory effects section, perhaps you can see why two reports of individual studies in "Web MD" and "TIME Health & Family" are not usable to rebut the conclusions of a secondary source in a scholarly journal? At least can you see that when the BBC juxtaposes the views of British Lung Foundation with those of Clear, "which used to be known as the Legalise Cannabis Alliance", it is engaging in journalism, not medical analysis? Do you anticipate any problem that TIME seemed to find it surprising that those who smoked cannabis 2-3 times a month didn't suffer from lung cancer at the same rate as those who smoked tobacco 8 times a day? You see, what we need is experts, not editors, to be doing the analysis of primary sources - and that's why we set so much value on the best of the secondary sources that we have available. If you know of an equally good source as Gordon (2013) that says something different - or criticises Gordon et al - then bring it up; it's how we can move forward in improving the article. Hope that helps --RexxS (talk) 18:36, 27 December 2013 (UTC)
 * I do have some concerns about using Gordon so extensively. He is an addiction specialist. His field does benefit financially from having marijuana use classified as problematic and detrimental. It is possible he is somewhat biased. For example, he suggests that marijuana causes bladder cancer. It seems he referenced only two studies for that claim. In one study, there was only one subject, someone who smoked 5 joints per day. This study is practically meaningless. The other study involved only 52 bladder cancer patients, all of whom were Vietnam vets and most were tobacco smokers. This is not at all a random sample, who knows how many unknown confounders war veterns may share. For one, they were likely exposed to the many chemicals used in that war including Agent Orange, Agent Blue, etc. They were asked about exposure but they cannot know if they were exposed for certain, especially if they bought pot from the locals (as most soldiers did) which could easily be contaminated. Only six subjects (11 percent) admitted to having used marijuana and not tobacco, not a large sample. There simply is not much evidence here to conclude much at all. Add to that an emerging study showing reduced risk of bladder cancer: here or here. I'm not saying the Gordon review is without value, I just question if some of the claims should be included in the article when the "association" is weak at best. Specifically, the liver cancer claim (see this new study), the bladder cancer claim, and the Lung cancer claim (the International Lung Cancer Consortium does not seem to think it causes lung cancer). I am not saying Gordon's work has been successfully refuted by these primary sources and marijuana does not cause these cancers, I am merely questioning whether they should be mentioned at all considering such weak associations. — Preceding unsigned comment added by Psyden (talk • contribs) 18:46, 27 December 2013 (UTC)
 * When those new primary sources are reviewed by secondary reports, they'll be included (and I doubt it will be long, since there is so much attention to cannabis research relative to any other topic I usually work on). In the meantime, we follow guideline and alert our readers to what the most recent, highest quality sources say; it's not our job to play doctor and provide amateur analysis of secondary sources, much less our own views on unreviewed primary sources.  Sandy Georgia  (Talk) 18:51, 27 December 2013 (UTC)
 * Gordon's literature review "surveyed the peer-reviewed medical literature from 1998 to 2013 of studies assessing the association of marijuana use and physical diseases". It's very specific to the question of the effects of cannabis on physical health, so it's hardly surprising that it has several things to say about those issues. As it is published in a respected scholarly journal, it carries the authority of its peer-reviewers and the editorial process of the journal, whose job it is to examine the very questions that Psyden raises. Our job as editors is to evaluate the quality of the sources - using our policies and guidelines to help us - not provide our own critique of the author's methods, a job we have no demonstrable qualifications to undertake.
 * WP:MEDASSESS tells us "Several formal systems exist for assessing the quality of available evidence on medical subjects. "Assessing evidence quality" means that editors should determine the quality of the type of study. Editors should not perform a detailed academic peer review. Do not reject a high-quality type of study due to personal objections to the study's inclusion criteria, references, funding sources, or conclusions." --RexxS (talk) 19:32, 27 December 2013 (UTC)
 * Thank you for your answers. I will read the guidilines, but I think it should be wiser if I took care of similar pages on it.wiki. It's been too long since I contributed on wiki, and I am probably a bit rusty. Not being a mothertongue doesn't help either. MarkyRamone92 (talk) 19:57, 27 December 2013 (UTC)
 * WP:MEDASSESS tells us "Several formal systems exist for assessing the quality of available evidence on medical subjects. "Assessing evidence quality" means that editors should determine the quality of the type of study. Editors should not perform a detailed academic peer review. Do not reject a high-quality type of study due to personal objections to the study's inclusion criteria, references, funding sources, or conclusions." --RexxS (talk) 19:32, 27 December 2013 (UTC)
 * Thank you for your answers. I will read the guidilines, but I think it should be wiser if I took care of similar pages on it.wiki. It's been too long since I contributed on wiki, and I am probably a bit rusty. Not being a mothertongue doesn't help either. MarkyRamone92 (talk) 19:57, 27 December 2013 (UTC)

Lede
As Alexbrn pointed out, the Lede needs to summarize what is in the body. I've removed diff the quotation about liver damage, etc., until it is expanded in, and in alignment with, the body. There is no mention of liver damage in the article.

""A 2013 literature review said that exposure to marijuana had biologically-based physical, mental, behavioral and social health consequences and was "associated with diseases of the liver (particularly with co-existing hepatitis C), lungs, heart, and vasculature". The authors cautioned that "evidence is needed, and further research should be considered, to prove causal associations of marijuana with many physical health conditions"."


 * The liver damage claim should be left out one way or the other. There is a large new study claiming that is does not cause liver damage. Psyden (talk) 15:21, 24 December 2013 (UTC)
 * Per WP:MEDRS, we shouldn't use unreviewed primary sources to refute secondary sources. Sandy Georgia  (Talk) 16:38, 24 December 2013 (UTC)

Is "associated with" really a strong enough claim to warrant inclusion in the Lede? Further, is this claim in alignment with what we've got in the body now? It seems a better summary would be, "much research has looked at the possible link between cannabis and diseases of the ..." and then state whether any causal links were found. This quotation probably fits better within the body rather than the Lede, unless it perfectly summarizes the body.  petrarchan47  t  c   08:14, 24 December 2013 (UTC)
 * I have moved this material to the body; it can be summarized in the lede if necessary (BTW, not sure if simply deleting this content was a good idea, particularly since in doing so you broke some other references in the article). Alexbrn talk 08:22, 24 December 2013 (UTC)
 * I didn't mean to disrupt anything, but as you know, the guidelines state that the Intro needs to be a summary, and can't introduce novel content. If the lede is to mention liver damage, we'd better have a section talking about it, and not simply a mention in a quote. Also, again, I do wonder if associations are strong enough to include in the body. It wouldn't seem so. In fact, if all we have are associations, a statement needs to be made about that. What can we say definitively about the effects of cannabis? This is what the reader wants to know, this is what they should read in the intro.  petrarchan47  t  c   08:29, 24 December 2013 (UTC)
 * Yup, the lede needs work and this should really follow the article body itself getting into better shape. I have added a bare-bones summary of Gordon for now so it isn't quite so hopelessly inadequate. Alexbrn talk 08:37, 24 December 2013 (UTC)
 * But why, as an NPOV editor, would you leave out the neutral and positive effects mention? It's fine, I'll re-add it but please, this is getting exhausting. We have to cover the whole story here. I don't understand why I am the only editor saying this.  petrarchan47  t  c   09:29, 24 December 2013 (UTC)
 * The lede summarizes the body; we don't "pick" what to put in based on an assessment (which I don't make or understand really) about whether information is "positive". By accurately summarizing the article body in the lede we will automatically get a neutral lede; giving undue weight to small aspects of the body in the lede risks it being not neutral. Alexbrn talk 09:40, 24 December 2013 (UTC)
 * You also must realize that your group just swept through the entire suite of articles and now they are indeed heavily negative. But if MEDRS is saying that there are positive and neutral effects, you must realize that the editors have obviously missed something, and haven't presented good, unbiased coverage here. I am not going to make any headway if you revert every one of my edits as if I have no idea what I'm doing. I feel as if I am being toyed with, and I am fully aware that when you're well connected and have a bunch of editing friends, you can get away with anything here. I am just asking nicely not to put me through this, and really help tell the full story, the negative, positive and neutral aspects as they appear in RS. And, if RS is saying that NIDA impacts the coverage, we say that too.  petrarchan47  t  c   09:50, 24 December 2013 (UTC)

It is unhelpful to focus on editors and their imagined conspiracies. The problem here is your use of this source. Read it through in full and you will see that the phrase you cherry-picked out of the middle of it (to support the position that "there are positive and neutral effects") is in no way a duly fair representation of its overall position. If there are health benefits to using cannabis, and you want that reported here, then it is really very simple: bring forth the good sources saying that and represent them accurately. Alexbrn talk 12:02, 24 December 2013 (UTC)
 * The problem, in my humble opinion, is that this article deals with the long-term effects of cannabis, and the sources tell me that they are overwhelmingly potentially negative: dependency; exacerbation of psychosis in susceptible individuals; association with tobacco and the damage that causes; possible damage to a fetus and the developing adolescent brain. Of course, you have to have a perspective: most cannabis users probably won't see any ill-effects, so we have to be careful in our summaries not to over-simplify. But what benefits does long-term cannabis use bring? You could argue that it has potential value in treating (or at lest helping cope with) many conditions - MS is an obvious example - and CBD has undoubted anti-inflammatory and anti-psychotic properties, but that's for the Medical cannabis article, as I'm unaware of any treatment that's been shown to rely on a long-term effect of cannabis. That's the problem with having so many different articles: the reader can't see the whole picture because somebody decided to splinter the topics into isolated areas. I'm sorry you find my contributions failing to be "good, unbiased coverage" - I'll try to do better. I will suggest more text for the lead after I've had a chance to do some work on the later sections of this article. --RexxS (talk) 15:06, 24 December 2013 (UTC)
 * Positive long term effects should at least be mentioned briefly here to balance out the article. A link to Medical cannabis should be posted for readers who desire more information. Psyden (talk) 15:10, 24 December 2013 (UTC)
 * What positive long term effects? The link to Medical cannabis is in the See also section, which is where we put links to related articles for readers who desire more information. --RexxS (talk) 15:35, 24 December 2013 (UTC)
 * I'm pretty sure that Sanjay Gupta is not the answer, especially with a grocer's apostrophe. Alexbrn talk 15:41, 24 December 2013 (UTC)
 * A chief of Neurosurgery, a surgeon general candidate, and CNN's chief medical correspondent is an adequate source for the claim that the large majority of research is looking for detrimental effects of cannabis Psyden (talk) 15:49, 24 December 2013 (UTC)
 * No it isn't - certainly not in the lead. Gupta's opinion piece on CNN is not authoritative enough to make a sweeping statement like:
 * "The large majority of studies have investigated the detrimental effects of long-term cannabis use, while some have investigated it's[sic] benefits."
 * I understand the argument that in the USA, there may be a governmental bias against research into positive effects of cannabis and its derivatives. But what of Canada, the UK, India, Holland? - are we suggesting that NIDA exerts a malign influence over research throughout the world? And what has it to do with the long term effects of cannabis? --RexxS (talk) 15:53, 24 December 2013 (UTC)
 * And Germany (which has produced some infamous primary sources that haven't stood up to secondary scrutiny). Sanjay Gupta is a TV personality, and has none of the attributes associated with high-quality secondary reviews; using him as a source in an encyclopedia would be an embarrassment.  Sandy Georgia  (Talk) 16:40, 24 December 2013 (UTC)

National Institute on Drug Abuse... is reluctant to support medical research and has historically focused its efforts (almost) exclusively on demonstrating the drug's harmful effects. According to Ware et al, most cannabis research in the United States occurs “under a paradigm of prohibition and the study of risk is not yet balanced by much-needed research on benefits.” PUBMED 3538401

The summary for the "Adverse effects of cannabis" study being used in the lede also talks about this problem with research. I haven't heard any complaints about the fact that the Adverse effects review, or most of the other sources in these articles, have research that comes from the US. I don't think editors need to prove whether most science comes from the US in order to add this, MEDRS is making the case, so it makes sense to add it here for context. Many scientists and researchers are arguing that the funding creates biased results, and these are the same results that end up in this article. I've added it back to the lede, reversing Rex who complained about the CNN source, so I've added MEDRS instead.  petrarchan47  t  c   10:09, 4 January 2014 (UTC)
 * Still undue US-centric opinion for the lede (and still with grocer's apostrophe). (Add: and sourced to a 1986 article on cells in Chinese?) Alexbrn talk 10:15, 4 January 2014 (UTC)
 * No, it isn't undue. But I meant to use a Mayo clinic review, I got my wires crossed apparently. Please stop with the "too US-centric" argument. This claim only goes one direction. You would never complain to Sandy about her use of the American Psychiatric diagnostic manual to speak about all cannabis dependency worldwide, nor her use of it in the summary for this article at the main Effects article. Never would you remove it or mention that it's a good example of synth, and says nothing about dependency in the first place. In the same way, I think you will never allow one of my edits to remain on this page longer than 5 minutes. And I don't think this editing behaviour is based in some deep concern for neutral, fully flushed-out cannabis articles  petrarchan47  t  c   11:03, 4 January 2014 (UTC)
 * Here is a better ref: PUBMED 3538401    petrarchan47  t  c   11:05, 4 January 2014 (UTC)
 * You are again focusing on editors rather than content, which is problematic. (And FWIW, I have complained about "negative" FDA material in the lede as being US-centric, so even your bad faith narrative isn't consistent). I don't know why you think your undue content with uncorrected grammar flaws and the wrong citation should be allowed to stand. Also, you are converting what appears in the source as opinion about the US ("According to Ware et al ...") into a universalized statement of fact in Wikipedia's own voice ("The large majority of studies have investigated the detrimental effects of long-term cannabis use"). So this is not neutral either. Alexbrn talk 11:40, 4 January 2014 (UTC)
 * I will assume for the moment that you are here to help build an informative article. Instead of fighting with you, I will let you add this information yourself, I left MEDRS here. I am glad you have dropped the US-centric argument, and note you have no rebuttal about your uneven editing behaviour. Again I remind you, read the summary for your beloved Adverse effects review that you all had quoted in the Lede, complete with "liver damage" not mentioned in the body. In the summary they mention straight away that the legal scene in the US hampers the ability to obtain badly-needed research. A vast majority of reviews I've seen mention this. Further, the initial entry by another editor of this material used CNN - which is RS for the statement being made. But there are ample sources to create a nice section about this matter. Enjoy,   petrarchan47  t  c   12:17, 4 January 2014 (UTC)
 * Maybe we should have a section that talks about cannabis research. We should mention that the source for most of the research in this article comes from the U.S. (not surprising since the U.S. does the most medical research) and it is biased toward finding negative aspects. Psyden (talk) 13:28, 4 January 2014 (UTC)
 * I'm having difficulty finding the source you're talking about to justify adding "The large majority of studies have investigated the detrimental effects of long-term cannabis use, while some have investigated it's[sic] benefits." to the lead. Would it be possible when you suggest a source, you explicitly specify what it is? I think you're suggesting that we add something along the lines of:
 * "The US Drug Enforcement Agency (DEA) has been criticised for continuing to classify marijuana as an illegal Schedule I drug, whereas its value in alleviating muscle spasms due to multiple sclerosis, chronic pain and nausea has been recognised by the medical community. Also the the federal restriction that the National Institutes of Health controls funding clinical studies in the US make it difficult for researchers to investigate the beneficial effects of cannabis."
 * cited to:
 * Now that would give me two problems: (1) what part of the article would that be summarising if we include it in the lead?; (2) What has it to do with the long-term effects of cannabis? The entire article only mentions 'long-term' once: "Marijuana does reduce some eye pressure associated with glaucoma; however, the effects were short-term, and did not outweigh the long-term hazards of using the drug." Is that what you want us to say here?
 * I think it would be a useful addition to whatever article deals with research into benefits/medicinal uses of cannabis, but I struggle to find any long-term effects of cannabis that have beneficial value. There's far too much muddled thinking in many of these articles and it would be useful to consider just what the scope of each one should be. I can understand that you feel that cannabis has unjustly been given a bad reputation in the US, and you want to right that great wrong, but indiscriminately pushing a line in multiple unrelated articles doesn't help. It just creates conflict with editors who want to keep the articles focussed on their topic. Now that the holidays are over, I'll find time this coming week to go through the rest of this article with a view to finding the best sources and summarising them as neutrally as I can, bearing in mind principally WP:MEDRS, WP:DUE and WP:ASF. I'd be more than happy to read any good-quality sources you'd suggest (but please no more 30-year old studies on sinus nodal cells in Chinese). When we can all agree that the main part of the article properly covers what those sources say, I'll make some suggestions about what might be summarised in the lead. How does that sound? --RexxS (talk) 03:38, 5 January 2014 (UTC)
 * You can take a look at what sources say regarding research here. This is a complex field, and it is not surprising you have yet to come across a great deal of research covering the long term positive effects of cannabis, and there is a reason for that, besides Project Medicine's relatively new arrival to this subject. The "Adverse effects" review talks about the US law restricting needed research in the third paragraph of its conclusion: "...more research is required. The research may be difficult in the current political climate of the USA[127]. We found much of the existing literature lacking good, sound evidence. We concur with many of the authors that there are significant problems with the evidence presented." The conclusion to the Adverse review has not been well-covered here (at least not the last time I checked), especially in comparison to the author's remarks in the introduction, which were quoted verbatim in the Lede but not mentioned in the body (specifically, the liver damage claim). Let's do consider the scope of this article: Long-term effects. What I have seen is that PM has grasped on to the Adverse effects, juicing that one review article for everything negative, and leaving this and related articles heavily slanted in the process. Editors who wish to build this article are free to add information about research restrictions to the body, and then mention it in the Lede.  petrarchan47  t  c   00:48, 9 January 2014 (UTC)
 * You can take a look at what sources say regarding research here. This is a complex field, and it is not surprising you have yet to come across a great deal of research covering the long term positive effects of cannabis, and there is a reason for that, besides Project Medicine's relatively new arrival to this subject. The "Adverse effects" review talks about the US law restricting needed research in the third paragraph of its conclusion: "...more research is required. The research may be difficult in the current political climate of the USA[127]. We found much of the existing literature lacking good, sound evidence. We concur with many of the authors that there are significant problems with the evidence presented." The conclusion to the Adverse review has not been well-covered here (at least not the last time I checked), especially in comparison to the author's remarks in the introduction, which were quoted verbatim in the Lede but not mentioned in the body (specifically, the liver damage claim). Let's do consider the scope of this article: Long-term effects. What I have seen is that PM has grasped on to the Adverse effects, juicing that one review article for everything negative, and leaving this and related articles heavily slanted in the process. Editors who wish to build this article are free to add information about research restrictions to the body, and then mention it in the Lede.  petrarchan47  t  c   00:48, 9 January 2014 (UTC)

Dependency section
As I was going through the citations to flag the secondary reviews per WP:MEDRS, I encountered this text in the section on "Dependency" (which I have now renamed from "Cannabis dependency" per WP:MSH):

I've moved this text here for clarification: Sandy Georgia (Talk) 16:42, 11 December 2013 (UTC)
 * 1) First, it should be six, not 6, per WP:ORDINAL.
 * 2) Next, the text was attributed to NIDA, but cited to the New York Times, and sourced to a non-profit advocacy organization called DrugSense.  What the heck.
 * So, I went looking and found the NY Times text at
 * which doesn't mention cannabis.
 * 1) Per WP:EL, we should avoid linking to websites that have copyvio, so besides that we shouldn't generally be citing an advocacy organization for medical content, we certainly shouldn't be citing this one, that contains copyvio.  So, what is the source of this text to begin with (NIDA?), and
 * 2) Why is this even here?  Why are we using a 1994 NYTimes piece, when we have secondary reviews covering the same territory?
 * 1) Per WP:EL, we should avoid linking to websites that have copyvio, so besides that we shouldn't generally be citing an advocacy organization for medical content, we certainly shouldn't be citing this one, that contains copyvio.  So, what is the source of this text to begin with (NIDA?), and
 * 2) Why is this even here?  Why are we using a 1994 NYTimes piece, when we have secondary reviews covering the same territory?
 * It must of been a reference to this chart by Dr's Henningfield and Benowitz: http://www.legacy.library.ucsf.edu/documentStore/h/i/r/hir19e00/Shir19e00.pdf Psyden (talk) 20:18, 11 December 2013 (UTC)
 * Thanks, Psyden ... the plot thickens. The online archive of NYT doesn't have that; maybe it was filed with them under a different title?  And UCSF also has a copyvio.  Yikes.  So, all things considered, why don't we use a journal source for this text and avoid the problem of trying to sort this mess out?  Sandy Georgia  (Talk) 20:46, 11 December 2013 (UTC)
 * Apparently the NY Times does not include charts or pictures in their text-only archives. A reproduction would need to be ordered There is another scan here though not much clearer. If a better source cannot be found, it sounds like Wikipedia use would constitute fair use Psyden (talk) 21:27, 11 December 2013 (UTC)
 * Generally, because of the licensing requirements here, Fair Use doesn't work as an argument, but I'm glad you uncovered the possible source of the problem. I'm pretty sure we can locate similar text in any number of journal reviews; the gist is that there are other substances that are more addictive, and we don't really need the one through six ranking (which according to what I've read in recent reviews may no longer be accurate).  I will look around as soon as I get a free moment .  Sandy Georgia  (Talk) 21:48, 11 December 2013 (UTC)
 * This may help, or not... "A number of investigators have addressed this issue and found that only a relatively small percentage of those who try marijuana will become addicted. For example, in a large-scale survey published in 1994 epidemiologist James Anthony, then at the National Institute on Drug Abuse, and his colleagues asked more than 8,000 people between the ages of 15 and 64 about their use of marijuana and other drugs. The researchers found that of those who had tried marijuana at least once, about 9 percent eventually fit a diagnosis of cannabis dependence. The corresponding figure for alcohol was 15 percent; for cocaine, 17 percent; for heroin, 23 percent; and for nicotine, 32 percent. So although marijuana may be addictive for some, 91 percent of those who try it do not get hooked. Further, marijuana is less addictive than many other legal and illegal drugs." Scientific American. According to Johns Hopkins, caffeine addiction rate appears to be 9% as well. It would be fair to say that cannabis and caffeine addiction rates appear to be similar.   petrarchan47  t  c   22:39, 11 December 2013 (UTC)
 * We don't need to cite to a magazine when our secondary reviews cover this ... I know one of the recent reviews had similar numbers, read it last night as my bedtime reading. (With about 30 recent reviews sitting on my desktop, it's sometimes hard to re-find things right away.) The Johns Hopkins source does not mention cannabis; stringing together sources to reach a conclusion is synthesis-- we have sources that cover everything without having to resort to synthesis or magazines.  I've listed a number of freely available sources at User:SandyGeorgia/Cannabis sources, and will be glad to add any new ones uncovered-- perhaps others will help find a source for this or similar text among those I've listed.  Sandy Georgia  (Talk) 23:10, 11 December 2013 (UTC)
 * I am aware of synthesis. This was a response to the text quoted above, which adds caffeine into the equation, but which the Scientific American article leaves out. If you have sources for all of this, why don't you add it back to the article (or maybe you have)?  petrarchan47  t  c   23:28, 11 December 2013 (UTC)
 * Re: "recent reviews may no longer be accurate", Sandy, do you have sources that contradict what I quoted just above, what is contained in the quote box at top? Do you have a problem with adding context to the addiction rate by comparing with other addictive substances, and if so, why?  petrarchan47  t  c   23:32, 11 December 2013 (UTC)
 * Yes, I do. Was posting one when we edit conflicted.  Let me see if I can resurrect it.  We can't add caffeine in on our own, that is synthesis.  Sandy Georgia  (Talk) 23:36, 11 December 2013 (UTC)
 * Sorry, in the edit conflict, I missed one question above ("If you have sources for all of this, why don't you add it back to the article (or maybe you have)?") I read the bulk of the sources while I was having my hair done, if you must know, and I couldn't add information then. :) :)  And I read more sources at bedtime as I get them; I've been busy just trying to keep up here. There is waaaaay too much information for me to add it all, across all of the articles, with several dozen reviews to sort and weigh, which is why I keep asking people to read those that are freely available and help out.  I can remember what I've read, but finding it again takes longer.  Sandy Georgia  (Talk) 23:42, 11 December 2013 (UTC)

(after edit conflict) I will put what I find here as I find it (it may take me some time):
 * Borgelt 2013
 * So the 9% reported in 1994 above, is reported in 2013 as 10-20% based on newer 2008–2010 data. I will post more as I find it.  Sandy Georgia  (Talk) 23:37, 11 December 2013 (UTC)

(after edit conflict)


 * I just saw the dependency section. For some reason that can only be explained by SYNTH, it begins with "Cannabis is the most widely used illicit substance in the world". And? OH! We are supposed to surmise from that that its addictiveness clearly causes this high rate, and this is so obvious no source is required that makes this connection for us. The other sentence states: "the DSM-5 categorizes cannabis addiction as one needing treatment". Sounds pretty serious. I can see why a comparison to caffeine addiction and a look at the comparable rates would not be a good fit here.  petrarchan47  t  c   23:39, 11 December 2013 (UTC)
 * Now, that's an attitude. I don't "surmise" anything I just say what the sources say.  Sandy Georgia  (Talk) 23:45, 11 December 2013 (UTC)
 * What does that source have to do with addiction, a relationship indicated by placement in the "Dependency" section?   petrarchan47  t  c   23:53, 11 December 2013 (UTC)
 * I'm sorry, but I'm not following your question. The source says:  "... of whom 10–20% will develop cannabis dependence. Among people admitted to substance treatment facilities "  Cannabis dependence, in the Dependency section of a cannabis article, talking about admittances to substance treatment facilities.  I'm missing the question, I guess.  Sandy Georgia  (Talk) 00:04, 12 December 2013 (UTC)

The difference in rates may have to do with how "addiction" is categorized: "The Science of Marijuana is written by Leslie L. Iverson, a professor of pharmacology at the University of Cambridge in England. In the book, he reviews decades of international research on marijuana, both laboratory research and survey research. Based on his review of the scientific literature, between 10 to 30% of regular users will develop dependency. Only about 9% will have a serious addiction..." Psychology Today. (Btw, for discussion on the talk page, it is perfectly acceptable to use sources that may not be useable for the article.)  petrarchan47  t  c   23:53, 11 December 2013 (UTC)
 * Also of note, it seems common for articles discussing cannabis dependence to compare it with other drugs, and our coverage here should reflect coverage in RS.  petrarchan47  t  c   23:56, 11 December 2013 (UTC)
 * The article you cite mentions a book published in 2008. A book published in 2008 will be based on data older than 2008.  The 2013 Borgelt source specifies the data it uses, as 2008 thru 2010. We should use our most up-to-date sources.  And then we say what they say ... if they don't use the word "addiction", we don't use the word addiction, but our article should still just reflect what the most recent, highest quality sources say.  This combativeness is an exhausting way to work on articles; I'll post more from sources another day.  Sandy Georgia  (Talk) 00:08, 12 December 2013 (UTC)
 * The dependency section is an example of summary style and therefore briefly summarises the content of the daughter article Cannabis dependence as indicated by the main template. We need to ensure that the content remains synchronised between these two articles, so the proper place to discuss changes to wording is Talk:Cannabis dependence. You may wish to discuss here the choice of what is contained in this article's summary, but it would be inappropriate to introduce new material not present in Cannabis dependence.
 * As for the question of comparing the rates of acquired dependency of cannabis and caffein, just find a MEDRS-compliant source that examines that comparison. In order to retain perspective, I assume we'll also need to find MEDRS-compliant sources that compare the potential for harmful effects of the two drugs? --RexxS (talk) 00:13, 12 December 2013 (UTC)
 * And that's another reason I don't just add things as I find them in many cases; this whole suite of articles first needs to be rationalized, and then the text added to the right article, and then summarized back to the main articles. The entire suite has duplicate text across many articles. Doing it slowly, right the first time, is easier.  I've for now focused on rooting out the very old primary sources, as I read through and sort the newer reviews ... as there is sooooo much to be done in here.  It is hard to understand how this entire suite of articles got into such bad shape.  Sandy Georgia  (Talk) 00:48, 12 December 2013 (UTC)

PMC3202504 "Marijuana may produce mild dependence in humans. This was shown to depend on the personality type of the addicts, and can be successfully reversed by abstinence or treated by cognitive-behavioral therapy, without the occurrence of major withdrawal symptoms."  petrarchan47  t  c   08:27, 12 December 2013 (UTC)
 * Kogan & Mechoulam 2007 (PMC3202504) looks like a decent overview, although it's getting a little long-in-the-tooth now. It's certainly preferable to some of the ancient primary sources deployed in Cannabis dependence, so it might be worthwhile seeing if covers issues not discussed by Gordon 2013 and using it to improve that article. I honestly don't think there's much point in trying to tinker with the "Dependency" section here until its main article is cleaned up and settles down. --RexxS (talk) 09:03, 12 December 2013 (UTC)
 * Suddenly there is no reason to 'tinker' here, and we are leaving it as is? This section makes Wikipedia an embarrassment. NIDA says dependency rate is 9%, and that is what is quoted by all the experts. I am not sure how Sandy's version is the one approved and allowed to remain on the page as it is not in keeping with the majority of MEDRS, and is stated less like an encyclopedia and more like a 1950's anti-drug brochure:
 * Cannabis is the most widely used illicit drug in the Western world, and in the US 10 to 20% of consumers who use cannabis daily become dependent. Cannabis use disorder is defined in the fifth revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as a condition requiring treatment.
 * I don't know why we can't say what MEDRS says, which is that 9% will develope dependency. Further, the DSM changed their definition of dependency, which is when cannabis and gambling became qualified. This understanding should be added, as there is talk of a distinction with cannabis between a psychological dependence and a physical one. I prefer exploring issues rather than the stubby coverage Project Medicine has left us with. This coverage is obviously designed to make the most negative statement possible.
 * What MEDRS says:
 * "9% of cannabis users develop cannabis dependence"
 * "Rather than focusing on physical dependence, the phenomenology of addiction broadened to include such constructs as compulsivity, loss of control, consequences, salience, and relapse. DSMIII codified a view of substance dependence for which symptoms of physical dependence were neither necessary nor sufficient for establishing a diagnosis. Among regular cannabis users, a dependence syndrome very similar to that described for other drugs of abuse was reliably described."
 * (regarding Adverse effects - which is now this article's focus) "it remains possible that the observed [adverse] associations result from convergent risks and common predisposing factors, as much as direct effects of cannabis use." PMC 3371269   petrarchan47  t  c   22:34, 9 January 2014 (UTC)
 * I reject your unwarranted attack on other editors - the reason the article has been cut back is that it was riddled with inaccurate information culled from news reports and uncritical acceptance of any pro-cannabis propaganda that could be found. You're the editor who read Budney et al (2007) Marijuana Dependence and Its Treatment and all you could find from it about dependency was . You should be ashamed of such blatant POV-pushing, considering that the article is principally concerned with describing how difficult it is to treat cannabis dependency - especially as the article doesn't even mention psilocybin, mescaline, or LSD. You dredged up someone else's sound-bite, then looked for a source to justify it, finding something from 2007 that makes a passing mention of half of the factoid you're trying to push. It's not how we write articles. We read the best quality sources and summarise them, not write what you think the article should say and then scratch around for sources in an attempt to justify that fixation.
 * It's interesting that Budney 2007 actually says "Marijuana produces dependence less readily than most other illicit drugs. Some 9 percent of those who try marijuana develop dependence compared to, for example, 15 percent of people who try cocaine and 24 percent of those who try heroin. However, because so many people use marijuana, cannabis dependence is twice as prevalent as dependence on any other illicit psychoactive substance (cocaine, 1.8 percent; heroin, 0.7 percent." because they also state that "During the past decade, marijuana use disorders have increased in all age groups. Contributing factors may include the availability of higher potency marijuana and the initiation of use at an earlier age. Among adults, marijuana use disorders increased despite stabilization of rates of use." and that "The percentage of substance abuse treatment admissions that were due to marijuana nearly doubled from 1993 to 2005." It looks like the percentage of users in the United States acquiring dependency has been on the increase over the last 20 years, so you ought not to be surprised that older sources quote a lower figure than newer ones. I wouldn't have had a problem with quoting 9% from a 2007 review if it wasn't for the fact that on the 11 December 2013 in this very thread, Sandy quoted Borgelt 2013 which now finds the rate to be between 10% and 20%.If you want to write something along the lines of "dependency rates among users in the United States used to be around 9%, but have now increased to between 10% and 20% (refs Budney 2007 & Borgelt 2013)", go ahead; it would be giving the reader a fuller picture, after all.
 * Again you bring forward a source Danovitch et al (2012) State of the Art Treatments for Cannabis Dependence and cherry-pick nuggets that suit your agenda. Did you not read the synopsis? "Cannabis dependence poses some distinct challenges for treatment providers ... the comparatively lower “severity” of cannabis-associated consequences makes it more difficult for some users to recognize the impact of their use and establish an enduring commitment to change ... the high prevalence of cannabis dependence, its strong association with co-morbid mental health problems, and the difficulty of achieving cannabis cessation ensure that many psychiatrists will face patients with cannabis dependence." Danovitch 2012 is about the problems involved in developing new treatments that are effective in helping those who have cannabis dependency. Why aren't your contributions reflecting the thrust of that? --RexxS (talk) 04:53, 10 January 2014 (UTC)
 * There seems to be some confusion of the reported dependence rates. The 9% figure is for people who ever try cannabis, the 10-20% figure is for DAILY users. Psyden (talk) 05:08, 10 January 2014 (UTC)
 * That's because most would assume we are speaking about the number of folks who will become addicted, without that caveat that this only applies to those who already smoke every day. Why not be more direct and say "9%", with the added information about higher rates with daily use after that? This is yet another tweak to the article that paints cannabis in a more negative light. A slight twist to the wording gets much juicier numbers, but we are now out of alignment with RS, which rarely mentions anything but the 9 or ten percent.   petrarchan47  t  c   04:38, 13 January 2014 (UTC)
 * Yes, that's how it is worded in the main dependency article. It should be worded similarly here, it is currently somewhat misleading. Psyden (talk) 04:51, 13 January 2014 (UTC)
 * And why do you think the wording was changed to be more convoluted and misleading? Would this reworking of coverage exist if it showed Cannabis in a less-negative light? I am simply unwilling to waste my time doing edits with a team bent on a certain POV. If this section is to be amended, it should be done by that team. Otherwise, from everything I have observed, it is most likely going to be reverted.  petrarchan47  t  c   20:47, 13 January 2014 (UTC)
 * And why do you think the wording was changed to be more convoluted and misleading? Would this reworking of coverage exist if it showed Cannabis in a less-negative light? I am simply unwilling to waste my time doing edits with a team bent on a certain POV. If this section is to be amended, it should be done by that team. Otherwise, from everything I have observed, it is most likely going to be reverted.  petrarchan47  t  c   20:47, 13 January 2014 (UTC)

Interesting article on where the 9% figure everyone has quoted for years came from. 9 Percent of Those Who Use Cannabis Become Dependent' Is Based on Drug War Diagnostics and Bad Science. I'm surprised this has not been examined more closely addressing some of issues Dr. Aggarwal has mentioned. Psyden (talk) 17:15, 30 January 2014 (UTC)

Lung cancer
While reviewing Psyden's comments about the International Lung Cancer Consortium above, I looked for the source and found a paper presented to the Annual Meeting 2013 of the American Association for Cancer Research. This turns out to be the same source as is used in our article and it's a decent-sized pooled analysis from reputable sources: It finds "no significant association between the intensity, duration, or cumulative consumption of cannabis smoke and the risk of lung cancer overall or in never smokers". That differs from Gordon's conclusions, so we should turn to our guidance for what to do when MEDRS-compliant sources disagree: attribute and summarise each of them (WP:YESPOV gives the policy). I was pleasantly surprised to see that our article already does just that - and adds in the differing views of the British Lung Foundation as well. The point is this: I can't see a problem with that section; three quality sources say different things, so we give the readers what the sources say and let them form their own conclusions. Are there any suggestions that we need to improve it? --RexxS (talk) 21:08, 27 December 2013 (UTC)
 * What I liked about the previous version of this and related articles (previous to Project Medicine's takeover) was that we gave the reader all sides of the story - and with cannabis research, it is often the case that studies will be all over the map. I do prefer to give the reader as much information as possible, and leave the conclusion to them unless it is well established in RS. Unfortunately, 90% of my additions since PM took ownership of these articles have been reverted. And no, it's not because I was lacking proper MEDRS. If interested, take a look at the collection of 'not negative' MEDRS I've collected, and see whether this side of the issue is being well-covered by PM.  petrarchan47  t  c   00:29, 9 January 2014 (UTC)
 * The goal is not to make a collection of 'not negative' sources (or 'negative' ones) to mine, but to find the best sources period. By summarizing what they say fairly one automatically gets a neutral article. Coming at this with a pre-baked idea of what the "sides of the story" are that need representing is inherently problematic. Alexbrn talk 07:24, 9 January 2014 (UTC)
 * The collection was made in response to the work done by Project Medicine on all of the cannabis articles, which looked to me to be a collection of the worst-claims-available. I noticed a lack of neutral or positive effects, and an unwillingness to have their existence mentioned. I suggested above that those interested could take a look at the collection, and I am unsure how you read it as anything else. Your participation here is not indicative of an editor interested in building this article with studies (regardless of how they portray the subject). You spend more time arguing and reverting than researching and adding by a long shot, and seem to only function as a security guard for the work of your team, now that it's finished.  petrarchan47  t  c   02:36, 10 January 2014 (UTC)
 * These general, personalized complaints are unhelpful. You say "looked to me to be a collection of the worst-claims-available" and again that speaks of a problem: sources should be assessed on their quality, not on their supposed POV. If you have a specific concern about a source and/or the way it is cited, then what is that concern? Let's focus on content. Alexbrn talk 05:59, 13 January 2014 (UTC)
 * I have had no indication that my time and effort will be rewarded with fair treatment. To address what your team has done to the entire suite of articles is a giant mission. But even focusing on one small section has been both time-consuming and entirely fruitless, and not because my sources are bad or non-neutral. This is why I've suggested to takeover by Project Medicine be reviewed by ArbCom. Your recent WikiHounding by visiting obscure articles that I've worked on should also be reviewed. Activity like that puts all else an editor does into question.  petrarchan47  t  c   20:39, 13 January 2014 (UTC)
 * Some bizarre words, but no content proposal. This does not help. If you cannot WP:FOC there is nothing more to be said here. Alexbrn talk 20:46, 13 January 2014 (UTC)
 * No offense, but on the outside looking in, you're the one who isn't being neutral, and your edits on other articles show a rather argumentative bent. Sorry, but when a person is causing the problem, there's not much that people with an interest in providing others with information can do other than inform that person that they're causing a problem and hope they stop.75.140.96.40 (talk) 03:08, 10 February 2014 (UTC)

Neutrality
I think this article represents the negative health effects of cannabis very well, though it makes little to no mention of the positive effects observed in research. There are lots of studies available on the matter, here are a few that I found within 10 minutes:

Cancer:

Inhibition of colon carcinogenesis by a standardized Cannabis sativa extract with high content of cannabidiol.

Cannabis extract treatment for terminal acute lymphoblastic leukemia with a Philadelphia chromosome mutation.

Cannabidiolic acid, a major cannabinoid in fiber-type cannabis, is an inhibitor of MDA-MB-231 breast cancer cell migration.

Non-THC cannabinoids inhibit prostate carcinoma growth in vitro and in vivo: pro-apoptotic effects and underlying mechanisms.

Cannabinoids: a new hope for breast cancer therapy?

Towards the use of non-psychoactive cannabinoids for prostate cancer.

Epilepsy:

Cannabidiol exerts anti-convulsant effects in animal models of temporal lobe and partial seizures.

'''[http://www.ncbi.nlm.nih.gov/pubmed/17609644 Marijuana: an effective antiepileptic treatment in partial epilepsy? A case report and review of the literature.]'''

Report of a parent survey of cannabidiol-enriched cannabis use in pediatric treatment-resistant epilepsy.

Multiple Sclerosis (MS):

Cannabidiol provides long-lasting protection against the deleterious effects of inflammation in a viral model of multiple sclerosis: a role for A2A receptors.

What place for ▾ cannabis extract in MS?

Treatment of spasticity in multiple sclerosis: new perspectives regarding the use of cannabinoids

Parkinson's Disease:

The multiplicity of action of cannabinoids: implications for treating neurodegeneration.

Survey on cannabis use in Parkinson's disease: subjective improvement of motor symptoms.

Cannabis in movement disorders.

Depression:

Study: cannabis a double-edged sword (This study found a pronounced anti-depressant effect at low doses, though large doses worsened it)

Antidepressant-like effect of Δ9-tetrahydrocannabinol and other cannabinoids isolated from Cannabis sativa L

I think it should also be noted that many of the studies indicating a carcinogenic or otherwise deletrious effect are in regards to smoked cannabis (and often cannabis smoked via the more common means instead of vaporization, which may produce less carcinogenic byproducts than cannabis smoked via flame-heating). I think this point should be emphasized, as it is already well established that inhalation of smoke released from combustion is often toxic, so it's not unreasonable to assume that a large portion or all of the organ damage associated with cannabis use might be from it's use via combustion instead of oral or vaporization. Further research is definitely justified.

I'm not disputing the negative effects outlined in this article, as they're well founded. I do believe the article needs much more coverage of the investigated positive effects, as well as clarifying that it is not yet clarified if the method of consumption affects the toxicity of regular cannabis use. LiamSP (talk) 02:46, 24 February 2014 (UTC)
 * There are long-term positive effects? Any reliable (i.e. WP:MEDRS) sources for that? Alexbrn talk 05:21, 24 February 2014 (UTC)
 * Aside from the point that this article is concerned with long-term effects of cannabis, not Medical cannabis, all of the reports you've listed are primary studies. It's worth reviewing the advice given in WP:MEDRS to understand why we strongly prefer to use secondary sources. Our article has 12 sources marked as "review" or "meta-analysis" and they seem to me to present a fairly consistent picture of the long-term effects of cannabis - which I hope our article reflects reasonably accurately - even if they don't have much positive to report. If you know of any equally-good-quality recent secondary sources that deal with other aspects of the long-term effects of cannabis, then please let's use them. I've had no luck yet in finding the positive long-term effects of cannabis in a secondary source and I've put a lot more time than 10 minutes into searching. --RexxS (talk) 15:59, 24 February 2014 (UTC)

Merge two section
I think the sections title 'Lung' and 'Respiratory Effects' should be merged. I realize the lung bit is under cancer but the repisratory effects section seems to add little that couldn't be included in the Lung Section. ACanadianToker (talk) 03:49, 28 May 2014 (UTC)
 * One section is about lung cancer which is different than respirtory effects so IMO they should be kept seperate. Doc James  (talk · contribs · email) (if I write on your page reply on mine) 10:50, 28 May 2014 (UTC)

British Lung Association report
There is absolutely nothing in the sources here to support the use of the word "controversial" in describing the BLA report: It is not unusual for supporters of cannabis use to criticise such reports, but the BLA 2012 report is a good MEDRS-compliant source and its criticism is undue for this article unless that criticism meets the same standards. It is not the place of Wikipedia to white-wash the effects of cannabis, but to report as neutrally as possible the conclusions of the best sources. We already have Gordon (2013), BLA (2012) and Zhang (2013) that represent the range of conclusions in the best sources. If there are other equally good sources that offer very different perspectives, then let's discuss them. --RexxS (talk) 18:14, 16 June 2014 (UTC)
 * The claim "the risk of developing lung cancer is nearly 20 times higher from smoking typical cannabis cigarettes" is not supported by their sources, or them in fact. Even the study on which it was based did not come to this conclusion and this study was refuted in the very same journal it was published. The BLF did not suggest that the cannabis risk was 20 times greater, they were merely talking about that one study. The BLF also states "However, studies in human populations have yielded conflicting evidence on the subject: some suggest there is a link between smoking cannabis and lung cancer while others don’t. In fact they sum up that section of the report with "Further research is needed to confirm these findings and to explain why smoking a cannabis cigarette MIGHT pose a greater risk than smoking a tobacco cigarette. Identifying the mechanisms by which the components of cannabis smoke MAY cause lung cancer is also crucial". — Preceding unsigned comment added by Psyden (talk • contribs) 21:37, 16 June 2014 (UTC)
 * From "The impact of cannabis on your lungs":
 * A rigorous case-control study by Aldington and colleagues in 2008 made significant progress in showing that the link exists. The authors analysed the smoking habits of people diagnosed with lung cancer and a control group without lung cancer. Their major finding was that smoking cannabis increases the risk of developing lung cancer in young adults. The study also suggests that smoking one cannabis cigarette a day for one year increases the risk of lung cancer by 8 per cent. Importantly, researchers took variables including tobacco smoking into account when calculating this figure. By way of comparison, the same study suggests that smoking one pack of tobacco cigarettes (20 cigarettes) a day for one year increased the risk of lung cancer by 7 per cent. This suggests that smoking just one cannabis cigarette increases the risk of developing lung cancer by a similar amount as smoking 20 tobacco cigarettes. The study also concluded that 5 per cent of lung cancers in those aged 55 or under may be caused by smoking cannabis.
 * The source clearly supports our text. We don't do amateur analysis of secondary sources to try to reach other conclusions; we summarise neutrally what the secondary source says. If you've got equally good sources that offer criticism of the source used, let's see them (and I don't mean a blog from a dissenter with an axe to grind). Now if you think that our summary of "The impact of cannabis on your lungs" in the Lung section doesn't represent neutrally what that report says, then feel free to propose different text, but their own first-page summary is quite explicit:
 * Current evidence shows that smoking cannabis is hazardous to our lungs. We know far less about the effects of cannabis smoke than the impact of tobacco smoke. However, there is evidence that cannabis smoking is linked to many adverse effects, including: chronic coughing; wheezing; sputum (phlegm) production; tuberculosis; legionnaires’ disease; aspergillosis; acute bronchitis; airway obstruction; pneumothorax, and lung cancer.
 * Your choice of quote and inaccurate emphasis on the words 'might' and 'may' COULD be construed as cherry-picking an unintended meaning from what is a common disclaimer suggesting further research would make clearer the conclusions. --RexxS (talk) 11:10, 17 June 2014 (UTC)
 * It does not at all support our text. Our text implies that the BLF concluded cannabis smoking has a 20 times greater risk of lung cancer when clearly they did not. Again, they were simply discussing one study, not concluding anything. The sentence in question needs to be removed or reworded. "A 2012 literature review by the British Lung Foundation found evidence that smoking cannabis is linked to lung cancer." would be a more accurate representation of this aspect of their report. Psyden (talk) 01:18, 18 June 2014 (UTC)
 * You mean that you feel:
 * This suggests that smoking just one cannabis cigarette increases the risk of developing lung cancer by a similar amount as smoking 20 tobacco cigarettes. - source
 * does not support:
 * A 2012 literature review by the British Lung Foundation suggested that the risk of developing lung cancer is nearly 20 times higher from smoking typical cannabis cigarettes than from smoking tobacco cigarettes - our text
 * It looks to me like it does support the text. BLF equates 1 cannabis cigarette with the same carcinogenic risk potential as 20 tobacco cigarettes. However, concentrating on that one part of the report could be seen as undue, so I have some sympathy with your suggested re-write. Wouldn't you say though, that your "linked to lung cancer" is a rather anaemic summary of "linked to many adverse effects, including: chronic coughing; wheezing; sputum (phlegm) production; tuberculosis; legionnaires’ disease; aspergillosis; acute bronchitis; airway obstruction; pneumothorax, and lung cancer"? How about replacing the sentence
 * "A 2012 literature review by the British Lung Foundation suggested that the risk of developing lung cancer is nearly 20 times higher from smoking typical cannabis cigarettes than from smoking tobacco cigarettes, due to deeper, longer inhalation and the lack of filters."[ref]
 * with:
 * "A 2012 literature review by the British Lung Foundation concluded that cannabis smoking was linked to many adverse effects, including bronchitis and lung cancer."[ref]
 * I suggest those two examples of adverse effects as I suspect that smoking almost anything is likely to be linked to coughing, wheezing, sputum, etc. but evidence of links to bronchitis and lung cancer is a rather more significant finding. What do you think? --RexxS (talk) 00:30, 19 June 2014 (UTC)
 * Yes. In their sentence:
 * This suggests that smoking just one cannabis cigarette increases the risk of developing lung cancer by a similar amount as smoking 20 tobacco cigarettes.
 * the word "this" refers to that one study (Aldington and colleagues), it is not the BLF's conclusion. So I feel your suggestion: "A 2012 literature review by the British Lung Foundation concluded that cannabis smoking was linked to many adverse effects, including bronchitis and lung cancer.", would better represent their findings.

Lung cancer 2
Hi, I'm wondering why the main part of 'Lung cancer' takes the BLF's 2012 report when some experts like David Nutt think it's just scaremongering. While the largest and longest study  isn't mentioned at all.Popelin (talk) 09:19, 25 May 2014 (UTC)
 * It's because we have agreed that we don't use a blog or a single study to refute a good quality secondary source. It's explained in detail at WP:MEDRS. --RexxS (talk) 20:57, 25 May 2014 (UTC)
 * Is this a primary or secondary ("data were pooled from 6 case-control studies") source ? Thanks. Popelin (talk) 19:53, 24 June 2014 (UTC)
 * It's a secondary source (indexed by Pubmed as ). Zhang et al took six studies to do their pooled analysis. I can't tell whether it's the highest quality of source, because it's not clear how the authors selected the six studies. It doesn't seem to have reached conclusions about much though. --RexxS (talk) 00:36, 1 July 2014 (UTC)
 * I've just realised: this is a reprint with an expanded analysis of http://cancerres.aacrjournals.org/cgi/content/meeting_abstract/73/8_MeetingAbstracts/3633 which is already used as a reference (current number 27) for the third paragraph of the Lung section. --RexxS (talk) 00:53, 1 July 2014 (UTC)
 * It's a secondary source (indexed by Pubmed as ). Zhang et al took six studies to do their pooled analysis. I can't tell whether it's the highest quality of source, because it's not clear how the authors selected the six studies. It doesn't seem to have reached conclusions about much though. --RexxS (talk) 00:36, 1 July 2014 (UTC)
 * I've just realised: this is a reprint with an expanded analysis of http://cancerres.aacrjournals.org/cgi/content/meeting_abstract/73/8_MeetingAbstracts/3633 which is already used as a reference (current number 27) for the third paragraph of the Lung section. --RexxS (talk) 00:53, 1 July 2014 (UTC)

clarification on edit, re smoking it
The study that talks about the possible risk of lung and prostate cancer is in the context of smoking cannabis--not consuming it as food, or drink. The links to cancers are from the smoke, and the way the article reads is currently misleading on this point. I tried to edit to correct his, but it was reverted. 67.180.77.106 (talk) 02:40, 17 June 2014 (UTC)
 * The study supporting the text that you altered is
 * You are completely wrong to assume that the review only considered the context of smoking cannabis, as a glance at the 127 references in that paper will show you. --RexxS (talk) 10:37, 17 June 2014 (UTC)
 * I read the review but I saw nothing about cannabis causing lung or prostate cancer from consuming it as a vegetable or juice drink, or even extracted oil. All the studies I've seen show that its protective against cancer. The only possible link was in the context of smoking as all combustion produces carcinogens. If I am wrong, then can you please point out where exactly does it say that edibles are also linked to cancer? I'd be very surprised given my knowledge on the subject. As it stands leaving this out, makes it misleading. 67.180.77.106 (talk) 22:34, 4 July 2014 (UTC)
 * "We surveyed the peer-reviewed medical literature from 1998 to 2013 of studies assessing the association of marijuana use and physical diseases. We conclude that healthcare providers should be cognizant that the existing literature suggests that marijuana use can cause physical harm." I can see where it states "we surveyed ... studies assessing the association of marijuana use and physical diseases" but I can't see anywhere that says "but only the ones where cannabis was smoked". Did you look at the list of studies that Gordon et al examined? Are you trying to claim that those sources were all only concerned with smoking cannabis? It's abundantly clear that Gordon's review examined cannabis use in all its forms, not just from smoking. I'm sorry that its conclusions don't fit your view of cannabis use, but that's what the literature says. Have a read of WP:MEDRS and see that we use secondary reviews to analyse primary studies, rather than relying on anonymous editors drawing conclusions from their personal experiences. --RexxS (talk) 23:48, 4 July 2014 (UTC)
 * No need to be sorry since we are humans and can interpret the rules in the spirit of the rules: to write a truthful and accurate Encyclopedia.  Truth matters, right?  It's simply not true that there are any studies which link consuming cannabis as an edible being  to causing lung or prostate cancer. Yet, this is what the current wording, implies. Thus it's misleading. I have studied the issue and reviewed the literature: the only such associations that exist to date pertain to smoking only. If that is not true, then please cite a study. Again, does the truth matter? I think so. So we should apply the rules in a way that serves what the evidence shows. My view of Cannabis IS based on what the literature does say. We should write in a clear way that elucidates this literature, instead of obfuscating it. The rules can be used either way. I'm for the former, which is the intelligent, intended, purpose of this, rule, i.e. to tell the truth--not hide behind misleading wordings that falsely imply that non-smoking cannabis consumption is linked to cancer when opposite is the truth of the matter. 67.180.77.106 (talk) 05:04, 13 July 2014 (UTC)
 * You are repeatedly saying that the studies do not specifically say that one specific intake causes two specific cancers. Then you say your "view of Cannabis IS based on what the literature does say." In this particular case, you are stating what you believe the literature does NOT say. Instead, we are focused on what it does say. For example, your most recent edit to the article indicated that a review article was discussing exposure to marijuana "smoke". However, the article discusses exposure to marijuana. While you are focused here on two forms of cancer, the article in question associates marijuana exposure with "diseases of the liver (particularly with co-existing hepatitis C), lungs, heart, and vasculature". - Sum mer PhD  (talk) 17:20, 13 July 2014 (UTC)
 * You are correct technically, however you miss my original point. Let me clarify. When I said my view is based on what the literature says, I was not only speaking of this one source--but looking at all the literature for years. You are right this particular study is does not specify form of intake. But it should because smoke is carcinogenic, and yet there are no studies the link the herb when its being consumed with cancer--only anti-cancer properties. That is why its a bad study to the extent that it conflating smoking (which everyone knows is bad) with the herb itself causing cancer. As editors, its our duty to report the best studies--not misleading ones. Or, if not, then we have a duty to be honest with the state of knowledge on the subject and issue a point of clarification should be made about this weakness,  and this should be found and cited--if this study is to be used, i.e. "oral ingestion use eliminates the need to inhale toxic combustion products created by smoking and therefore negates the risk of respiratory harm associated with cannabis smoking." Currently the way this is used,  falls short of the purpose of building an encyclopedia, which is to increase knowledge. Otherwise, we act like mindless robots following technical rules but abandoning common sense and logic. Lets not lose sight of the forest for the trees! 24.5.69.164 (talk) 22:40, 15 July 2014 (UTC)
 * "(D)iseases of the liver (particularly with co-existing hepatitis C), lungs, heart, and vasculature" ≠ "cancer". - Sum mer PhD  (talk) 02:00, 16 July 2014 (UTC)
 * But its located under the sub heading of "Cancer." And says, I quote, "marijuana could be carcinogenic," and "...bladder cancer does seem to be linked to habitual marijuana use, and that there may be a risk for cancers of the head and neck among long-term (more than 20 years) users.[2] Gordon and colleagues said, "there does appear to be an increased risk of cancer (particularly head and neck, lung, and bladder cancer) for those who use marijuana over a period of time..." So it is talking about cancer. My problem with this is the fact that there is no evidence that cannabinoids in themselves are carcinogenic, e.g. if administered orally or via other non-smoking related methods. In fact all the evidence shows its strong anti-cancer properties, which is why it researching thing it is likely that the anti-tumor activity of THC, CBD and other cannabinoids are responsible for reducing the risk from non-cannabinoid components of cannabis smoke.24.5.69.164 (talk) 22:14, 17 July 2014 (UTC)
 * "(D)iseases of the liver (particularly with co-existing hepatitis C), lungs, heart, and vasculature" ≠ "cancer". - Sum mer PhD  (talk) 02:00, 16 July 2014 (UTC)
 * But its located under the sub heading of "Cancer." And says, I quote, "marijuana could be carcinogenic," and "...bladder cancer does seem to be linked to habitual marijuana use, and that there may be a risk for cancers of the head and neck among long-term (more than 20 years) users.[2] Gordon and colleagues said, "there does appear to be an increased risk of cancer (particularly head and neck, lung, and bladder cancer) for those who use marijuana over a period of time..." So it is talking about cancer. My problem with this is the fact that there is no evidence that cannabinoids in themselves are carcinogenic, e.g. if administered orally or via other non-smoking related methods. In fact all the evidence shows its strong anti-cancer properties, which is why it researching thing it is likely that the anti-tumor activity of THC, CBD and other cannabinoids are responsible for reducing the risk from non-cannabinoid components of cannabis smoke.24.5.69.164 (talk) 22:14, 17 July 2014 (UTC)

New review
This 2013 review contrasts with Gordon and the BLA's conclusions about the correlation between cannabis and lung cancer. It reads "no clear link to chronic obstructive pulmonary disease has been established". Do you think it should be mentioned in the article?--MarkyRamone92 (talk) 16:37, 30 June 2014 (UTC)
 * Dr. Donald Tashkin is an expert who specializes the field of lung disease. The findings in his review should be mentioned. Psyden (talk) 19:12, 30 June 2014 (UTC)
 * Looks like a respectable expert opinion to me. I don't think it says anything about lung cancer that we don't already have cited to http://cancerres.aacrjournals.org/cgi/content/meeting_abstract/73/8_MeetingAbstracts/3633 although it would probably be useful in expanding the opening sentence in the Respiratory effects to point up Taskin's conclusion about COPD. --RexxS (talk) 00:47, 1 July 2014 (UTC)
 * You are right, Tashkin's findings are essentially similar to those by the International Lung Cancer Consortium regarding lung cancer; however, I think that the sentence "no clear link to chronic obstructive pulmonary disease has been established" adds something to the article, as there is no mention of the COPD in it.--MarkyRamone92 (talk) 07:03, 1 July 2014 (UTC)
 * I've of Respiratory effects to mention COPD and attributed Tashkin. --RexxS (talk) 14:05, 1 July 2014 (UTC)

Observation and suggestion. I am currently researching the effects of Medical Marijuana to determine if I want to try using it as an alternative treatment for my cancer. I don't want to smoke and have found that the other routes of administration are Oral and Vaporization (Heated below burning point thus almost no smoke carcinogens). Most of the info on this page seems to only apply to smoking. I would suggest separate sections the long term health effects for smoking vs those for other administration form or at least marking each entry/source as to weather it is based on Smoking, Oral, or other route of administration. RandomUnicorn — Preceding unsigned comment added by 24.2.55.112 (talk) 15:52, 15 September 2014 (UTC)

Skin Disorders
This recently added section has no reliable medical source per WP:MEDRS. Primary studies do no qualify and much of this is synthesis see "Synthesis of published material" WP:NOR. You would need a secondary source, like a review published in a respected medical journal. Here is a copy of the addition:

" Anecdotal evidence link cannabis consumption with premature ageing of the skin. Cannabis smoke, similar to tobacco smoke, contains hydrocarbons that suppress collagen production and hence contact with the skin has this effect. This symptom is not permanent and usually apparent in long term cannabis users. Users who smoke indoors or hotboxing experience this symptom more than users who smoke outside or somewhat protect their skin using moisturisers.

Long-term users of cannabis may also experience acne. Marijuana causes a small spike in testosterone immediately after administration, elevated testosterone levels are linked to increased Sebum production which in turn can lead to acne. Scientists say this is very unlikely to happen because very large quantities of marijuana are needed for this to happen. "

If you can find a reliable source we can add some of it back, but we do not publish anything comprised of "anecdotal evidence". I believe a few editors here had a list of acceptable sources, mostly reviews. Here is one: https://en.wikipedia.org/wiki/User:SandyGeorgia/Cannabis_sources Psyden (talk) 23:39, 11 November 2014 (UTC)
 * I have found this from huffingtonpost, I don't know what kind of source is this considered (secondary?) Life is too short to drink cheap wine. (talk) 20:49, 20 November 2014 (UTC)
 * Generally news articles are not very reliable medical sources. I guess if it where written by an expert in the field, like a doctor, it could be considered, but this one was not and Huntington Post is not a medical publication, which also weakens the quality of the source. The article really doesn't conclude much of anything anyway, it has a lot of "cannabis could do this or that, however...etc". We really should stick to the more well-established established conclusions otherwise our article could get out of hand quickly, filling pages with unsubstantiated theory and guesses regarding a very wide variety of potential effects. The best sources are those which are reviews published in respected medical journals such as those found on PubMed. For "publication type" search for "review", under "Title/Abstract" search for "Cannabis" (or "marijuana). I don't recall reading about skin aging and cannabis, but if the idea has merit and is supported by research, I would think a review must have at least mentioned it somewhere. Of course most of the research is focused on possible serious effects so it may be tougher to find.
 * I know, i use PubMed a lot, also LibGen is nice and there are many more of course. Well when i have done the research, it was months ago, i don't remember details, I think there was an in vitro study of cells exposed in marijuana smoke but my memory is foggy. If I find time I will have a look again. ;-) - Life is too short to drink cheap wine. (talk) 16:09, 5 December 2014 (UTC)

Critical review
I've read this critical review http://www.ncbi.nlm.nih.gov/pubmed/19586351 "Chronic toxicology of cannabis" I was especially concerned with the claims of reduced bone density of cannabis users and higher incidence of leukemia in offspring of cannabis using mothers. I did however realize that many sources are case reports or even animal studies, so not sources to be considered per WP:MEDRS. Nevertheless I think somebody with a medical background should look into this. Mikeschaerer (talk) 13:53, 17 December 2014 (UTC)
 * The scientific integrity of this author is very questionable. Dr. Stuart Reese has been accused of favoring faith based healing over science and has been accused of malpractice (Drug Free Australiaʼs Dr. Stuart Reece & Culpable Abuse Of Patients and Dr. Stuart Reece: Drug Free Australia’s shameful secret). Reese did not conclude much of anything regarding bones and more recent reviews such as Hall 2014 and Gordon 2013 have not even a mention of the word "bone" in them. The citation he gives for "severe bone loss" is a single case study that he did the same year of the review. The subject smoked a very unusually large amount of cannabis, up to 7g (1/4oz) cannabis daily for 25 years plus large amounts of hashish oil. Reese is also a member of "Drug Free Australia" which says something of bias. We have much more recent reviews of less questionable bias than this 2009 review, we probably do not need it. Psyden (talk) 15:26, 17 December 2014 (UTC)

British Lung Foundation Report
I strongly question the inclusion of the BLF's list of conditions that cannabis is "linked" to. They do not claim that cannabis causes these conditions and the evidence is borderline fear-mongering, as they | have been accused of in the past. For example,


 * Legionnaires disease - Their source for this is: 2010. Legionnaires disease in cannabis smokers. It only involves 3 case studies, all of whom were heavy cigarette and cannabis smokers.
 * Tuberculosis - This outbreak was not due to cannabis itself, but due to the sharing of cannabis pipes and "Shotgunning".
 * Aspergillosis - 1988. Fatal aspergillosis associated with smoking contaminated marijuana, in a marrow transplant recipient.. This is a single case study where a bone marrow recipient used contaminated cannabis.
 * Airway obstruction - They put this in their list this but state "Clearly, there is conflicting evidence about the effect smoking cannabis on its own has on lung function and the risk of developing COPD."

There is very weak support of their claims and nearly all are confounded by tobacco smoking. These facts are not represented in our text. Including claims with such weak support will in the long run only damage Wikipedia's reputation.Psyden (talk) 19:12, 29 January 2015 (UTC)


 * Hi
 * Let me start out by apologizing for that last revert.  I misread the source.  Generally I should not edit from my cell phone, it always seems to cause problems.
 * There are a number of issues I would like to discuss here, but rather than start with a wall of text, I'd like to start out by ascertaining whether we agree on the basic rules of WP:NPOV.  My understanding is something along the following lines:
 * When all reliable sources (in this case, WP:MEDRS compliant sources) agree, we state the common conclusion in Wikipedia's voice
 * When there is disagreement among reliable sources, we describe the varying opinions, giving weight to each POV according to its prevalence among reliable sources. Rather than speaking in Wikipedia's voice, we attribute each POV to its sources, as in "According to a review article published in the New England Journal of Medicine in 2013...."
 * There is no need to mention fringe points of view at all.
 * Are we in agreement so far?
 * The British Lung Association is clearly a reliable source for lung-health related information. So we should include their conclusions, and if others disagree, we can include those countervailing opinions too. The POV getting the most space is the one that is most prevalent.  The specific language used by the BLF is "established links" and I don't think we should try to soft-soap that.  If it is a minority position, the way to handle it is to include the other POVs and weight them according to their prevalence.
 * With respect to lung cancer, my read of the literature is as follows:
 * There are many reliable sources that state that cannabis smoke contains carcinogens, just like smoke from any other burned plant material
 * Most but not all WP:MEDRS compliant sources say that the evidence tying cannabis smoking is pretty thin
 * A few reliable sources tie these observations together by noting that cigarette smokers typically consume a pack or more a day, but most cannabis smokers consume far less cannabis than that and get much less exposure
 * With respect to other adverse effects on lung function, I think the consensus is mostly the other way.
 * There is the BLF citation above
 * This paper agrees with many of these points
 * A recent review in the NEJM states: "Marijuana smoking is also associated with inflammation of the large airways, increased airway resistance, and lung hyperinflation, associations that are consistent with the fact that regular marijuana smokers are more likely to report symptoms of chronic bronchitis than are nonsmokers42; however, the long-term effect of low levels of marijuana exposure does not appear to be significant.43 The immunologic competence of the respiratory system in marijuana smokers may also be compromised, as indicated by increased rates of respiratory infections and pneumonia.44 Marijuana use has also been associated with vascular conditions that increase the risks of myocardial infarction, stroke, and transient ischemic attacks during marijuana intoxication." (I can send you the paper if you don't have access)
 * Another recent review states: "There is unequivocal evidence that habitual or regular marijuana smoking is not harmless. A caution against regular heavy marijuana usage is prudent. The medicinal use of marijuana is likely not harmful to lungs in low cumulative doses, but the dose limit needs to be defined."
 * Shall we do our best to determine how prevalent these varying opinions are among reliable sources and write this up accordingly?
 * Best, Formerly 98 (talk) 22:01, 29 January 2015 (UTC)
 * Yes I agree (to the first 3 points you asked about. I got caught in an edit conflict). I think there is some confusion here. I was not saying to not include their position on lung cancer, my concern was in regard to their list of conditions including: Legionnaires disease, Tuberculosis, and Aspergillosis. I merely question the choice to include this part of their report with such weakly established associations. We cannot include everything by every source, we choose some of the best talking points and conclusions. If we are to include everything that cannabis could be linked to or associated with, it would fill pages with largely unsubstantiated claims (which is how this page was some time ago, both for and against harmful cannabis effects). I feel it is best to stick with more well-studied, and well-established associations. An association supported only by a few case studies is very weak, even if mentioned by a major health organization. While their inclusion might meet wiki guidelines, I do not feel that all of them add to the quality of this work.Psyden (talk) 23:26, 29 January 2015 (UTC)
 * Yes, it can be difficult because some subjects only seem to attract the attention of those on one side of the argument. I run across that all the time.  Do you want to draft some language including the references I listed above, and any others that you feel are worthwhile? I don't think we want to demonize smoking cannabis, but we should try to be even handed. There are SOME health risks here that should neither be overstated in a puritan frenzy nor should they be trivialized. People should make decisions on the best info available.  I try to do no harm.
 * The NEJM paper seems to corroborate the increased risk of lung infections. One issue I commonly come across is that certain drugs or behaviors increase the relative risk of certain adverse events, but the absolute risk remains fairly low.  So you might try to find some papers that give numbers for each of these.  I suspect that a  regular cannabis smoker has several times the risk of Aspergillis pnuemonia of a non-user, but if that smoker is 25 the absolute risk will still be very low.  If s/he is 70 however....
 * I am also a little concerned about the language regarding cannabis and risk of schizophrenia. It seems a little weasel-ish the way the current language bends over backwards to say "Cannabis doesn't cause schizophrenia, it only increases the risk in people who already have predisposing factors".  If you think about it, all that statement really says is that less than 100% of people who smoke cannabis get schizophrenia.  Because if only 90% of people who smoke cannabis become schizophrenic, then one can say that those who got it must have predisposing factors the other 10% didn't have, right?  Can we try to find a number for the extent to which cannabis increases the risk and get rid of the weasel language?  Thanks
 * Formerly 98 (talk) 00:03, 30 January 2015 (UTC)
 * Legalizing Cannabis: A physician’s primer on the pulmonary effects of marijuana elaborates on cannabis and its association with some of these respiratory effects. On page 202:
 * "it has been suggested that development of bullous disease and subsequent pneumothorax is related to inhalation techniques of marijuana resulting in barotrauma. Common techniques involve deep inhalation to hold smoke in the lung, performing a Valsalva maneuver"
 * "However, clinical evidence of increased incidence of pulmonary infections as a result of marijuana use is less robust and largely anecdotal. A few case reports have documented occurrence of aspergillosis related to marijuana use in immunocompromised patients"
 * "In these case reports, the pulmonary infections have been attributed to the contamination of marijuana by fungi and to the fact that marijuana is smoked without a filter. This has been confirmed by studies performed by Verweij et al. [28] who cultured samples of tobacco and marijuana for mold. Marijuana was found to be heavily contaminated with both Penicillium species and Aspergillus fumigatus"
 * "Marijuana inhalation techniques have also been linked to the transmission of tuberculosis"
 * "“Hotboxing” is another method of recreational marijuana use reported to facilitate transmission of tuberculosis"
 * Instead of just giving a list, how about we elaborate on some of these effects and their etiology?
 * May I suggest: "Smoking cannabis has been linked to adverse respitory effects including: chronic coughing, wheezing, sputum production, and acute bronchitis. (cite BLF) It has been suggested that the common practice of inhaling cannabis smoke deeply and holding breath could lead to pneumothorax. In a few case reports involving immunocompromised patients, pulmonary infections such as aspergillosis have been attributed to smoking cannabis contaminated with fungi. The transmission of tuberculosis has been linked to cannabis inhalation techniques, such as sharing water pipes and 'hotboxing'.(cite A physician's primer)"
 * (airway obstruction and lung cancer were already discussed in other sections). I have not had time to look into the schizophrenia section yet. Psyden (talk) 18:34, 30 January 2015 (UTC)
 * Sounds very reasonable, though if we could put something together along those lines citing the review articles we have discussed above, I like that a little better than citing books (other than textbooks). I see some pretty wild stuff getting published in books and I don't really think of them as RS unless a textbook anymore.  But thank you for your efforts here! Formerly 98 (talk) 20:52, 30 January 2015 (UTC)
 * I'm not sure I follow, "A physician's primer", the source I used is one of the review articles discussed above that you posted (thanks), it is published in a peer-reviewed medical journal. Perhaps something from the NEJM review that talks about prevalence would a good addition? ie: "however, the long-term effect of low levels of marijuana exposure does not appear to be significant (re: inflammation of the large airways, increased airway resistance, bronchitis)"? Psyden (talk) 22:07, 30 January 2015 (UTC)
 * Ok, stupid me. Forgot and thought it was the title of a book.  I need to slow down! Formerly 98 (talk) 01:26, 31 January 2015 (UTC)

New review
Full text available and I've added the Laysource parameter to show how one also links to press coverage of a secondary review. Sandy Georgia (Talk) 04:44, 20 May 2015 (UTC)

causation vs. correlation
This article doesn't do a good job of distinguishing between causation and correlation. Use of the phrases "increased risk" (Depressive disorder), "worsen the occurrence" (Mania symptoms) and "increases the risk" (Suicidal behavior) asserts causality instead of accurately discussing correlation. It is just as, if not more, likely that persons with depression, mania or suicidality are using cannabis to cope with these conditions than that the cannabis is causing or contributing to these conditions (i.e. increasing the risk or worsening the occurrence). Let's talk about it and see if we can make more accurate descriptions. 74.42.81.206 (talk) 06:08, 16 February 2015 (UTC)nate vazquez
 * Ideally the article should reflect the language of the sources. Sizeofint (talk) 21:56, 4 March 2016 (UTC)

Twisted Article
This is one of the most twisted articles I've read on wikipedia. Let me get this straight? webmd is a valid source of clinical research? Smoking Grass does not cause COPB so all that coughing you see with users coughing up blood is what then?

---pfff — Preceding unsigned comment added by 96.57.23.82 (talk) 16:25, 13 September 2015 (UTC)


 * I assume you mean COPD? Coughing has many causes, coughing up blood is not a symptom of COPD. The COPD claims are not sourced to WebMD. Psyden (talk) 16:08, 10 March 2016 (UTC)

Proper sourcing
Editors, before adding content please refer to WP:MEDRS. Medical claims have different sourcing requirements than other wiki content. Secondary reviews published in respected medical journals from the last 5 years are good sources. Primary studies alone, news articles, etc are not good sources and will usually result in deleted content. Psyden (talk) 16:11, 10 March 2016 (UTC)
 * I don't understand. The references were taken from a section on the Depersonalisation page. If the references are valid there, why are they not as valid here? Luxorbostian 00:29, 12 March 2016 (GMT)
 * They are not valid on that page either. I do not edit that page however. Psyden (talk) 00:36, 12 March 2016 (UTC)

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New study
https://www.ncbi.nlm.nih.gov/pubmed/28734078 --Mikeschaerer (talk) 11:12, 8 August 2017 (UTC)
 * Interesting, but it appears to be a primary source. We'll have to wait for a review that covers it. Sizeofint (talk) 17:49, 8 August 2017 (UTC)

Overall Tone of Article and Veracity of Information
Wow. Just wow. Is this Wikipedia? This article is so obviously slanted against cannabis use that it rivals governmental and treatment-industry propoganda. I direct your attention to such obvious lies as "...and in the US 10 to 20% of consumers who use cannabis daily become dependent." Really? A 20% dependency rate? That's laughable. And the one accurate fact cited - the zero mortality rate - was only done so begrudgingly, surrounding it with weasely language suggesting that a lack of sufficient research renders that fact as suspect. 184.98.96.86 (talk) 20:12, 4 March 2016 (UTC) MrNaturalAZ 20160304
 * I do not believe that the general public will take much of this article seriously. While most claims are properly sourced, its tone is approaching that of NIDA propaganda. Much of the article mentions claims that are inconclusive, out of context, rarely occur, etc. Confounding is rarely eliminated and evidence is weak for many claims. Some claims are likely simple associations, yet many readers will interpret this as implying causation. These points are not always made clear to the reader. Psyden (talk) 15:59, 10 March 2016 (UTC)
 * Our recreational drug articles in general leave a lot to be desired. Unless someone like you cares a whole awful lot, nothing is going to get better... it's not. Sizeofint (talk) 17:53, 10 March 2016 (UTC)
 * I have to agree - it is hard to take this article seriously. Someone should balance it out at this point. 71.237.26.253 (talk) 00:45, 31 July 2017 (UTC)

Bad Article
Why is there no information about the health benefits assoicated with use? And also that studies that allege some harmful effects---this fails to mention that its the smoke, not the cannabinoids themselves, which have any known links to cancer. In fact, studies have shown they have strong anti-cancer/anti-tumor properties. Came to this article and only found one sided, slant ed, and bad info. This article needs expansion. 2601:645:8302:842F:C06:55B2:F8B:716 (talk) 22:42, 24 July 2016 (UTC)
 * Well, psychoactive drug articles are pretty crappy in general on Wikipedia. I agree it needs work. When dealing with medical content we use the WP:MEDRS sourcing guideline. This restricts some of the sources we can use. You're welcome to improve this article as long as it stays within MEDRS. Sizeofint (talk) 02:23, 25 July 2016 (UTC)

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Lead
There have been a couple of attempts to change the lead. If it is to be changed, any claims need to reflect the current research and where disputed or unproven (the large majority of it) this needs to be mentioned. For example:

"Many scientists have developed a hypothesis that cannabis is a gateway drug, meaning the usage of cannabis allows for interest in potentially stronger drugs"

This is untrue. Many scientists have backed away from the 'gateway theory'. It is for the most part a simple association with limited evidence showing causation. A recent review,Vanyukov et al., 2012, denounces the gateway theory "The promotion of the erroneous gateway theory ultimately does the public a disservice, including the hindering of intervention". When confounding factors, such as: peer drug use, personal and social conditions, gender, age, marital status, mental disorders, family history of substance abuse, overlapping illegal drug distribution channels, alcohol use disorder, nicotine dependence, ethnicity, urbanicity, and educational attainment are appropriately measured and considered little causative effect remains for the simple association.

"Cannabis is comprised of two active ingredients: delta-9-THC and cannabidiol otherwise known as CBD. Delta-9-THC is responsible for the "high" users experience while consuming cannabis, while cannadidiol is responsible for the temporary sensation of pain relief and decreased anxiety that users experience during consumption"

This is also untrue. THC and CBD have both been shown to alleviate pain and other medical symptoms. Also there are many other cannabinoids in cannabis besides THC and CBD. Some psychoactive, some medically useful.

This is a complex subject with little conclusive research. This does not leave much for the lead, the lead should be kept simple for this reason. Psyden (talk) 21:02, 11 November 2018 (UTC)

Am I smoking the same cannabis?
I just wanted to say I am a long term cultural user of cannabis and whenever I read the "claimed" side effects I want to ask what the hell were they smoking during these studies. Seriously some of the findings seems absurd when you have been using this plant on a daily basis for years. I mean it's like how a coffee drinker can tell you that you don't experience a moment of insanity when you drink a strong cup. Although that is the findings of coffee well if my dagga brains serves me correctly.

I would like to point out a simple oversight made by most of the studies and research on the negative side-effects of cannabis and that is they are using a single strain of cannabis or do not account for strain type at all. (especially older studies)

There are probably thousands of strains of cannabis. Each one unique with it's own unique cannabinoid profile exerting different properties and physiological changes on the human body.

Cannabis is not a single strain where you can generalize short & long term effects as if it each study or finding applies to all cannabis strains.

How is the accounted for, has this been anticipated?

-- Mickey  ☠  Dangerez  00:53, 16 September 2017 (UTC)
 * Reference: The 2nd paragraph of the Effects of cannabis highlights the problem with outdated research. References must be re-verified as accurate to current scientific consensus.-- Mickey  ☠  Dangerez  01:06, 16 September 2017 (UTC)
 * The best course of action would be to find some WP:MEDRS compliant sources and WP:FIXIT. If you don't have much experience editing medical content yet, you may want to post proposed changes here first to get feedback. Sizeofint (talk) 04:02, 16 September 2017 (UTC)
 * Thank you! Don't have any experience with writing medical content yet but will propose changes here first. have a great day. -- Mickey  ☠  Dangerez  08:52, 16 September 2017 (UTC)

Mickey, I do not necessarily think the differences between your experience and other's experiences is down to a 'single strain'. Your experience is a 'single case' and we are all biologically different people; single case reports are one of the weakest form of evidence. All psychoactive drugs have a side effect profile and I've never seen it described where 100% of persons get the exact same side effect or withdrawal effect profile or lack thereof. There is also the issue with long-term use where side effects will diminish for some people (tolerance) or increase or appear for others (toxicity or withdrawal). I am not denying that there are some subtle or not so subtle differences between strains of cannabis. There is additionally many controversial viewpoints on cannabis reflected in the academic literature.-- Literaturegeek |  T@1k?  11:27, 16 September 2017 (UTC)
 * Agreed! This is my problem exactly not even flowers from the same plant or strain has consistent levels of cannabinoids and terpenes and all of the chemicals that make up its composition throughout a crop, that should only show the complexity and difficulty of formulating studies where the quantity and locations of endo-cannabinoid receptors also differ from individual to individual. This is why academics and people with a formal qualification in science related to the field must review the references and information presented here and accommodate for this. I can only hope for scientific breakthroughs that would help clarify this further. What I am proposing is that the latest scientific consensus should apply where there is a contradiction to outdated information. The Afrikaans Wiki article for cannabis still contain unverified pseudo-scientific claims af:Dagga. Thank you for engaging in discussion.-- Mickey  ☠  Dangerez  12:13, 16 September 2017 (UTC)
 * Also think in terms of recreational alcohol. There are many various types of alcoholic beverages each one having it's own effects. Think beer vs hard liquor. Tequila vs Brandy. Some people get hammered by Tequila while having brandy tolerance. Altough alcohol is basic it does not differ as much as cannabis crops. Not all cannabis strains are equal. For example one would give your red dry eyes while another give cotton mouth. Logically it tells me that different cannabinoid receptors are targeted by different strains. Thus it's really not as subtle difference between crops and strains. I mean have a look at the strain chart and the effects they may have. It's bigger the the evolutionary wheel. :D -- Mickey  ☠  Dangerez  12:20, 16 September 2017 (UTC)
 * We just follow the most reputable mainstream sources and if they don't differentiate between types of cannabis/alcohol/tobacco (or whatever) when discussing harms, then Wikipedia won't either. Alexbrn (talk) 12:23, 16 September 2017 (UTC)
 * But they do differentiate on alcohol: beers vs alcohol. eg. 2 beers' debilitating effects is equal to 1 tot of hard liquor. (Hypothetical), just because they don't does not meen they shouldn't. Someone needs to inform researchers of this. Do they even know seeing they don't use it themselves to understand this complexity and may even be a major stumbling block that would excel cannabis research. All I am saying is question the questionable. Just for the sake of inspiring curiosity see this graph and realize even between plants, crops and strains the levels of these chemicals differ considerably. I think little research has really been done on the profiles of cannabis and it's effects. A major contradiction is the statement that cannabis causes, or may cause hallucinations. Although I am not contesting any specific point in the article from an anecdotal point of view and for someone involved in the cannabis culture. I have never heard of anyone experiencing hallucinations from cannabis. If this was a major characteristic of cannabis YouTube would filled with cannabis smokers "seeing things or hearing things". I just want people to think about some general blanket statements made about cannabis as if it's a single thing. Only the individual cannabinoids can be understood as a single thing as it is removed from the complexity.-- Mickey  ☠  Dangerez  12:47, 16 September 2017 (UTC)


 * Please see video: the Visualization of the endocannabinoid signaling system -- Mickey  ☠  Dangerez  12:57, 16 September 2017 (UTC)
 * Someone needs to inform researchers of this. Sure, but it isn't really Wikipedia's purpose to tell scientists what they should research. The best we can do here is include a "Research directions" section that discusses some of the prominent areas of new research. If assaying the effects of different cannabis strains is one of these we can mention it there. Do they even know seeing they don't use it themselves.... Given over 50% of Americans have used Cannabis at some point, I can virtually guarantee many researchers have as well. Sizeofint (talk) 17:08, 16 September 2017 (UTC)
 * hehehe, I am not speaking in capacity of Wikipedia but on behalf of humanity. Also promoting the discussion of cannabis and pushing for enlightenment on the subject in the hope that someone that has some connection to future research possible read this or also comes to the same realization. Even I am guilty of not realizing the complexity of the plant and is how I have come to this POV. Thank you for providing usable input. It is greatly appreciated.-- Mickey  ☠  Dangerez  19:10, 16 September 2017 (UTC)

Let us keep this art (and all other ones) WP compliant. Zezen (talk) 09:45, 20 November 2018 (UTC)

Dunedin Study - Meir et Al. 2012
I have integrated a study that has been influential to my belief that cannabis has harmful longterm effects on mental health, the title unequivocally takes a position: "Persistent cannabis users show neuropsychological decline from childhood to midlife"

The addition contrasts with the previous tepid take that fixates in the inconsistency between studies, instead of focusing into the aspects that have been consistently replicated.

One of the most starkly contradicting sources appears quite strong, albeit only as recent as 2018, it's a free form review of current literature on the subject by pharmacologists[1]. It proposes that the direction of causality is in reverse, that low intelligence causes cannabis use. The strongest sources of this review cited were:


 * A systematic review of 105 papers. I'm not sure whether this will side with the 2012 Dunedin Study or with the Pharmacologist's review. I hope I can read it soon, or somebody can take a look and integrate it themselves, to reduce the effect of my own biases.
 * A 2018 twin study Coauthored by the same lead of the 2012 dunedin study[2]. I have not been able to access the actual pdf, but by glancing the abstract, title and commentary from the 2018 review it seems consistent with the pharmacologist interpretation, that it contradicts her 2012 work and lends credence to the inverse causality hypothesis. (If anyone can upload it, or rent and check whether it does in fact contradict her earlier findings, I'd appreciate it, she might address some key points to this discussion in it.)

Objectivity aside, and original research mode on, my hypotheses so far are: A) Our knowledge on cannabis prior to 2012 was heavily flawed and recent advances in methodology or quantity of evidence have shed light into alternative explanations that contradict the cognitive decline hypothesis. B) Meier's 2018 work provides an explanation for the cotwin studies consiistent with her early findings, or otherwise limits their refutation to a smaller subset of her original claims. And that she was selectively misinterpreted by the Pharmacologists (note how her 2012 study wasn't cited at all), possible for the reasons put forward in Hypothesis C. C) In a shift related to the wide legalization of cannabis in the USA[3][4], economic incentives were formed for USA journal publishers to publish positive research on cannabis.

Whether option C is paranoic or not, the difficulty of dismissing it points to an underlying weakness of the cited corpus, which is almost predominantly USA-based. If someone knows of citable work not from the USA, it would help avoid such a bias, regardless of whether its recent legalization might have polluted the objectivity of their scientific journals. [1] https://link.springer.com/article/10.1007/s11481-018-9782-9#ref-CR14 [2] https://link.springer.com/article/10.1007/s11481-018-9782-9#ref-CR60 [3] https://en.wikipedia.org/wiki/Green_rush [4] https://en.wikipedia.org/wiki/Decriminalization_of_non-medical_cannabis_in_the_United_States#State_recreational_legalization_begins_(2012)

--TZubiri (talk) 08:50, 22 May 2020 (UTC)

Reread the abstract from Meier 2017/2018, her conclusion seems to reduce the errata to short term use in adolescence, rather than recanting all of her earlier findings:

"Short‐term cannabis use in adolescence does not appear to cause IQ decline or impair executive functions, even when cannabis use reaches the level of dependence."

https://onlinelibrary.wiley.com/doi/abs/10.1111/add.13946

Good news for adolescents with the desire to experiment and lots of confidence in their self-control abilities. Still looking bad for persistent adolescent users. --TZubiri (talk) 09:16, 22 May 2020 (UTC)

Cannabis
Marijuana causes memory-loss. It is not 100%-harmless.

This phenomenon of memory-loss is backed-up with substantial-evidence, of all kinds, including circumstantial.

Best wishes,

184.22.249.124 (talk) 01:56, 12 July 2020 (UTC)

" ... although in the United States 10 to 20% of consumers who use cannabis daily become dependent, it is different from addiction. [...] " ~ Wikipedia.

Whether cannabis addiction exists (not talking about dependency, here) or not is extremely disputed and controversial. This point needs refinement.

We need to reflect the controversy.

Best wishes,

184.22.249.124 (talk) 10:26, 14 July 2020 (UTC)

This is a little bit political, but some cultures (let's not get into specifics) do not have a healthy relationship with cannabis.

A huge issue with doing research about cannabis is the cultural-political baggage that is surrounding the issue.

Politics is not a field known for objectivity, facts, logic, clarity, caution, ethics, science, and where things make sense.

Summary: Cannabis (the topic of cannabis-legalisation is particularly bad here) is a deeply political issue and this often clouds research.

Please be civil and respectful in your replies. Thank you.

Good day and best wishes,

184.22.249.124 (talk) 16:55, 14 July 2020 (UTC)

This article is less biased than the french one, but it's still far from being neutral. I'm interested in neurological changes, not prohibition-era propagandist "science" from last millennium. The article is called "long-term effects", not "Negative long term effects". It's confusing effects from the ROA and effects from canabinoids themselves. Its repeatedly committing the "correlation isn't causation" mistake. There are things as absurd as "As of 2017 there is clear evidence that long term use of cannabis increases the risk of psychosis, regardless of confounding factors, and particularly for people who have genetic risk factors" (genetic risk factors IS a confounding factor...).

--81.153.74.11 (talk) 14:21, 14 January 2021 (UTC)

Recent changes about cannabis and addiction
With respect to the continued reversions to state that cannabis is non-addictive (& citations which even say within them, that cannabis IS addictive).

The citations used here, such as Borgelt et al, to say that cannabis is non-addictive, it states this within the Discussion section: "Other concerns about medical cannabis include the need for adequate monitoring and prevention of addiction"

There are many, many more citations than 4 out there, so I'm happy to include more than 4 but I had figured it was sufficiently greater than a citation that doesn't even agree with the statement it's being cited for.

1. "Cannabis Addiction and the Brain: a Review". Journal of Neuroimmune Pharmacology.

2. "Neuromorphological background of cannabis addiction". Brain Research Bulletin.

3. "Is marijuana addictive?". National Institute on Drug Abuse

4. "Neurochemical basis of cannabis addiction". Neuroscience.

All of the journals & sources I included as citations, are among the most prestigious publications & widely used sources all across Wikipedia. They're utilized by clinicians globally. I didn't include anything controversial clinically; this is scientific consensus.

I am a big fan of the r/leaves subreddit & all those wondering about their place in addiction & recovery, like those in that community, deserve to find info on Wikipedia that is objective & not rife with personal/very uncommon opinion.

Dlobr (talk) 07:52, 10 April 2021 (UTC)

Also, & just to be clear, even if we take the stance of "well, cannabis may technically be addictive from the research perspective" but not from the perspective of the common definition. That, is also not true. Addiction is commonly accepted as having the following primary characteristics: continued use/drug-seeking, tolerance, & avoidance of withdrawal symptoms. All of those factors are firmly & independently established for cannabis, in the literature & in anecdotes, for decades.

So even if the argument is that "addiction is a harsh term" & "cannabis addiction isn't so bad", that still doesn't address that it clearly is quite addictive.

I welcome & will read any highly-cited scholarly work that invalidates all of the studies above & many others - science involves adapting to new evidence when necessary. Dlobr (talk) 08:02, 10 April 2021 (UTC)


 * In Wikipedia we say what sources say: WP:NOR and the addiction statement is a quote from the source.


 * You seem to have some desire to make this a black and white issue of addictive/non-addictive; nowhere does it say that "cannabis is non-addictive" as you claim; again, we say what sources say: when the sources say that the issue is more nuanced, that is what is expressed with the quote. --- Avatar317 (talk) 04:53, 11 April 2021 (UTC)