Alcohol (drug)

Alcohol, sometimes referred to by the chemical name ethanol, is one of the most widely used and abused psychoactive drugs in the world and falls under the depressant category. The term "Alcohol and Other Drugs" (AOD) emphasizes this inclusion by grouping alcohol with other substances that alter mood and behavior. Alcohol is classified by the World Health Organization (WHO) as a toxic, psychoactive, dependence-producing, and carcinogenic substance.

While the terms "drug" and "medicine" are sometimes used interchangeably, "drug" can have a negative connotation, often associated with illegal substances like cocaine or heroin, which is why the alcohol industry may argue that "alcohol is not a drug" (Room et al. 2007).

The normalization of alcohol consumption, along with past misconceptions about its health benefits, also promoted by the industry, further reinforces the mistaken idea that it is not a "drug". Even within the realm of scientific inquiry, the common phrase "drugs and alcohol" persists. However, this phrasing implies that alcohol is somehow separate from other drugs.

Paradoxically, despite being legal, alcohol, scientifically classified as a drug, has demonstrably been linked to greater social harm than most illegal drugs. This contradicts the perception some hold of alcohol being a harmless substance.

Alcohol is found in fermented beverages such as beer, wine, and distilled spirit – in particular, rectified spirit, and serves various purposes; it is used as a recreational drug, for example by college students, for self-medication, and in warfare. It is also frequently involved in alcohol-related crimes such as drunk driving, public intoxication, and underage drinking. Some esoteric religions and schools incorporate the use of alcohol for spiritual purposes.

For roughly two decades, the International Agency for Research on Cancer (IARC), a World Health Organization (WHO) agency, has classified alcohol as a Group 1 Carcinogen. In 2023, the WHO declared that there is "no safe amount" of alcohol consumption without health risks. This reflects a global shift in public health messaging, aligning with the long-standing views of the temperance movement, which advocates against the consumption of alcoholic beverages. This shift aligns with the global scientific consensus against alcohol for pregnant women due to the known risks of miscarriage, fetal alcohol spectrum disorders (FASDs) and sudden infant death syndrome (SIDS), as well as for individuals under the legal drinking age.

WHO also highlighted a statistic: nearly half of all alcohol-attributable cancers in the WHO European Region are linked to alcohol consumption, even from "light" or "moderate" drinking – "less than 1.5 litres of wine or less than 3.5 litres of beer or less than 450 millilitres of spirits per week". This new information suggests that these consumption levels should now be considered high-risk. Many countries exceed these levels by a significant margin. Echoing the WHO's view, a growing number of national public health agencies are prioritizing complete abstinence (teetotalism) and stricter drinking guidelines in their alcohol consumption recommendations.

Alcohol has a variety of short-term and long-term adverse effects on health.

Short-term effects from moderate consumption include relaxation, decreased social inhibition, and happiness while binge drinking may result in generalized impairment of neurocognitive function, blackout, and hangover. Excessive alcohol intake causes alcohol intoxication characterized by unconsciousness or, in severe cases, death; in 2016, excessive alcohol use was responsible for 3.0 million deaths worldwide.

Long-term effects are considered to be a major global public health issue and includes alcoholism, abuse, withdrawal, fetal alcohol spectrum disorder (FASD), liver disease, hepatitis, cardiovascular disease (such as cardiomyopathy), polyneuropathy, hallucinosis, long-term impact on the brain (such as brain damage and dementia), and cancers such as breast cancer and head and neck cancer (especially laryngeal cancer).

Despite being a widespread issue, social stigma around problematic alcohol use or alcoholism discourages over 80% from seeking help.

Alcohol works in the brain primarily by increasing the effects of γ-Aminobutyric acid (GABA), the major inhibitory neurotransmitter in the brain; by facilitating GABA's actions, alcohol suppresses the activity of the CNS.

Dutch courage
Dutch courage, also known as pot-valiance or liquid courage, refers to courage gained from intoxication with alcohol.

Alcohol use among college students is often used as "liquid courage" in the hookup culture, for them to make a sexual advance in the first place. However, a recent trend called "dry dating" is gaining popularity to replace "liquid courage", which involves going on dates without consuming alcohol.

Consuming alcohol prior to visiting female sex workers is a common practice among some men. Sex workers often resort to using drugs and alcohol to cope with stress. Female sex workers in low- and middle-income countries have high rates of harmful alcohol use, which is associated with increased risk of risky sexual behavior.

Alcohol when consumed in high doses is considered to be an anaphrodisiac.

Criminal
Albeit not a valid intoxication defense, weakening the inhibitions by drunkenness is occasionally used as a tool to commit planned offenses such as property crimes including theft and robbery, and violent crimes including assault, murder, or rape – which sometimes but not always occurs in alcohol-facilitated sexual assaults where the victim is also drugged.

Warfare
Alcohol has a long association of military use, and has been called "liquid courage" for its role in preparing troops for battle, anaesthetize injured soldiers, and celebrate military victories. It has also served as a coping mechanism for combat stress reactions and a means of decompression from combat to everyday life. However, this reliance on alcohol can have negative consequences for physical and mental health. Military and veteran populations face significant challenges in addressing the co-occurrence of PTSD and alcohol use disorder. Military personnel who show symptoms of PTSD, major depressive disorder, alcohol use disorder, and generalized anxiety disorder show higher levels of suicidal ideation.

Alcohol consumption in the US Military is higher than any other profession, according to CDC data from 2013–2017. The Department of Defense Survey of Health Related Behaviors among Active Duty Military Personnel published that 47% of active duty members engage in binge drinking, with another 20% engaging in heavy drinking in the past 30 days.

Reports from the Russian invasion of Ukraine in 2022 and since suggested that Russian soldiers are drinking significant amount of alcohol (as well as consuming harder drugs), which increases their losses. Some reports suggest that on occasion, alcohol and drugs have been provided to the lower quality troops by their commanders, in order to facilitate their use as expendable cannon fodder.

Food energy


The use of alcohol as a staple food source is considered inconvenient due to the fact that it increases the blood alcohol content (BAC). However, alcohol is a significant source of food energy for individuals with alcoholism and those who engage in binge drinking; For example, individuals with drunkorexia, engage in the combination of self-imposed malnutrition and binge drinking to avoid weight gain from alcohol, to save money for purchasing alcohol, and to facilitate alcohol intoxication. Also, in alcoholics who get most of their daily calories from alcohol, a deficiency of thiamine can produce Korsakoff's syndrome, which is associated with serious brain damage.

The USDA uses a figure of 6.93 kcal per gram of alcohol (5.47 kcal per ml) for calculating food energy. For distilled spirits, a standard serving in the United States is 1.5 USoz, which at 40% ethanol (80 proof), would be 14 grams and 98 calories.

Alcoholic drinks are considered empty calorie foods because other than food energy they contribute no essential nutrients. Alcohol increases insulin response to glucose promoting fat storage and hindering carb/fat burning oxidation. This excess processing in the liver acetyl CoA can lead to fatty liver disease and eventually alcoholic liver disease.

Medical
Spiritus fortis is a medical term for ethanol solutions with 95% ABV.

When taken by mouth or injected into a vein ethanol is used to treat methanol or ethylene glycol toxicity when fomepizole is not available.

Ethanol, when used to treat or prevent methanol and/or ethylene glycol toxicity, competes with other alcohols for the alcohol dehydrogenase enzyme, lessening metabolism into toxic aldehyde and carboxylic acid derivatives, and reducing the more serious toxic effects of the glycols when crystallized in the kidneys.

Recreational
Drinking culture is the set of traditions and social behaviors that surround the consumption of alcoholic beverages as a recreational drug and social lubricant. Although alcoholic beverages and social attitudes toward drinking vary around the world, nearly every civilization has independently discovered the processes of brewing beer, fermenting wine and distilling spirits.

Common drinking styles include moderate drinking, social drinking, and binge drinking.

Drinking styles


In today's society, there is a growing awareness of this, reflected in the variety of approaches to alcohol use, each emphasizing responsible choices. Sober curious describes a mindset or approach where someone is consciously choosing to reduce or eliminate alcohol consumption, not drinking and driving, being aware of your surroundings, not pressuring others to drink, and being able to quit anytime. However, they are not necessarily committed to complete sobriety.

Binge drinking
Binge drinking, or heavy episodic drinking, is drinking alcoholic beverages with an intention of becoming intoxicated by heavy consumption of alcohol over a short period of time, but definitions (see here) vary considerably. Binge drinking is a style of drinking that is popular in several countries worldwide, and overlaps somewhat with social drinking since it is often done in groups.

Drinking games involve consuming alcohol as part of the gameplay. They can be risky because they can encourage people to drink more than they intended to. Recent studies link binge drinking habits to a decline in quality of life and a shortened lifespan by 3–6 years.

Moderate, responsible, and social drinking
Moderate drinking, responsible drinking, and social drinking are often used interchangeably, but with slightly different connotations:
 * Moderate drinking - strictly focuses on the amount of alcohol consumed, following alcohol consumption recommendations (typically 1-2 drinks per day). This is called "drinking in moderation".
 * According to the WHO nearly half of all alcohol-attributable cancers in the WHO European Region are linked to alcohol consumption, even from "light" or "moderate" drinking – "less than 1.5 litres of wine or less than 3.5 litres of beer or less than 450 millilitres of spirits per week". Light alcohol consumption showed no connection to most cancers, but a slight rise in the likelihood of melanoma, breast cancer in females, and prostate cancer in males was observed. However, moderate drinking is associated with a further slight increase in cancer risk.  Also, moderate drinking may disrupt normal brain functioning.
 * Responsible drinking - as defined by alcohol industry standards, often emphasizes personal choice and risk management, unlike terms like "social drinking" or "moderate drinking."
 * Critics argue that the alcohol industry's definition does not always align with official recommendations for safe drinking limits.
 * Social drinking - refers to casual drinking of alcoholic beverages in a social setting (for example bars, nightclubs, or parties) without an intent to become intoxicated. A social drinker is also defined as a person who only drinks alcohol during social events, such as parties, and does not drink while alone (e.g., at home).
 * While social drinking often involves moderation, it does not strictly emphasize safety or specific quantities, unlike moderate drinking. Social settings can involve peer pressure to drink more than intended, which can be a risk factor for excessive alcohol consumption. Regularly socializing over drinks can lead to a higher tolerance for alcohol and potentially dependence, especially in groups where drinking is a central activity. Social drinking does not preclude the development of alcohol dependence. High-functioning alcoholism describes individuals who appear to function normally in daily life despite struggling with alcohol dependence.

Self-medication


The therapeutic index for ethanol is 10%.

Alcohol can have analgesic (pain-relieving) effects, which is why some people with chronic pain turn to alcohol to self-medicate and try to alleviate their physical discomfort.

People with social anxiety disorder commonly self-medicate with alcohol to overcome their highly set inhibitions. However, self-medicating excessively for prolonged periods of time with alcohol often makes the symptoms of anxiety or depression worse. This is believed to occur as a result of the changes in brain chemistry from long-term use. A 2023 systematic review highlights the non-addictive use of alcohol for managing developmental issues, personality traits, and psychiatric symptoms, emphasizing the need for informed, harm-controlled approaches to alcohol consumption within a personalized health policy framework.

A 2023 study suggests that people who drink for both recreational enjoyment and therapeutic reasons, like relieving pain and anxiety/depression/stress, have a higher demand for alcohol compared to those who drink solely for recreation or self-medication. This finding raises concerns, as this group may be more likely to develop alcohol use disorder and experience negative consequences related to their drinking. A significant proportion of patients attending mental health services for conditions including anxiety disorders such as panic disorder or social phobia have developed these conditions as a result of recreational alcohol or sedative use.

Self-medication or mental disorders may make people not decline their drinking despite negative consequences. This can create a cycle of dependence that is difficult to break without addressing the underlying mental health issue.

Unscientific


The American Heart Association warn that "We’ve all seen the headlines about studies associating light or moderate drinking with health benefits and reduced mortality. Some researchers have suggested there are health benefits from wine, especially red wine, and that a glass a day can be good for the heart. But there’s more to the story. No research has proved a cause-and-effect link between drinking alcohol and better heart health."

In folk medicine, consuming a nightcap is for the purpose of inducing sleep. However, alcohol is not recommended by many doctors as a sleep aid because it interferes with sleep quality.

"Hair of the dog", short for "hair of the dog that bit you", is a colloquial expression in the English language predominantly used to refer to alcohol that is consumed as a hangover remedy (with the aim of lessening the effects of a hangover). Many other languages have their own phrase to describe the same concept. The idea may have some basis in science in the difference between ethanol and methanol metabolism. Instead of alcohol, rehydration before going to bed or during hangover may relieve dehydration-associated symptoms such as thirst, dizziness, dry mouth, and headache.

Drinking alcohol may cause subclinical immunosuppression.

Spiritual


Spiritual use of moderate alcohol consumption is found in some religions and schools with esoteric influences, including the Hindu tantra sect Aghori, in the Sufi Bektashi Order and Alevi Jem ceremonies, in the Rarámuri religion, in the Japanese religion Shinto, by the new religious movement Thelema, in Vajrayana Buddhism, and in Vodou faith of Haiti.

Pregnancy


In the US, alcohol is subject to the FDA drug labeling Pregnancy Category X (Contraindicated in pregnancy).

Minnesota, North Dakota, Oklahoma, South Dakota, and Wisconsin have laws that allow the state to involuntarily commit pregnant women to treatment if they abuse alcohol during pregnancy.

Fetal alcohol spectrum disorder
Ethanol is classified as a teratogen —a substance known to cause birth defects; according to the U.S. Centers for Disease Control and Prevention (CDC), alcohol consumption by women who are not using birth control increases the risk of fetal alcohol spectrum disorders (FASDs). This group of conditions encompasses fetal alcohol syndrome, partial fetal alcohol syndrome, alcohol-related neurodevelopmental disorder, static encephalopathy, and alcohol-related birth defects. The CDC currently recommends complete abstinence from alcoholic beverages for women of child-bearing age who are pregnant, trying to become pregnant, or are sexually active and not using birth control.

Miscarriage
Miscarriage, also known in medical terms as a spontaneous abortion, is the death and expulsion of an embryo or fetus before it can survive independently.

Alcohol consumption is a risk factor for miscarriage.

Sudden infant death syndrome
Drinking of alcohol by parents is linked to sudden infant death syndrome (SISD). One study found a positive correlation between the two during New Years celebrations and weekends. Another found that alcohol use disorder was linked to a more than doubling of risk.

Adverse effects


Alcohol has a variety of short-term and long-term adverse effects. Alcohol has both short-term, and long-term effects on the memory, and sleep. It also has reinforcement-related adverse effects, including alcoholism, dependence, and withdrawal; The most severe withdrawal symptoms, associated with physical dependence, can include seizures and delirium tremens, which in rare cases can be fatal. Alcohol use is directly related to considerable morbidity and mortality, for instance due to intoxication and alcohol-related health problems. The World Health Organization advises that there is no safe level of alcohol consumption.

A study in 2015 found that alcohol and tobacco use combined resulted in a significant health burden, costing over a quarter of a billion disability-adjusted life years. Illicit drug use caused tens of millions more disability-adjusted life years.

Drunkorexia is a colloquialism for anorexia or bulimia combined with an alcohol use disorder.

Alcohol is a common cause of substance-induced psychosis or episodes, which may occur through acute intoxication, chronic alcoholism, withdrawal, exacerbation of existing disorders, or acute idiosyncratic reactions. Research has shown that excessive alcohol use causes an 8-fold increased risk of psychotic disorders in men and a 3-fold increased risk of psychotic disorders in women. While the vast majority of cases are acute and resolve fairly quickly upon treatment and/or abstinence, they can occasionally become chronic and persistent. Alcoholic psychosis is sometimes misdiagnosed as another mental illness such as schizophrenia.

An inability to process or exhibit emotions in a proper manner has been shown to exist in people who consume excessive amounts of alcohol and those who were exposed to alcohol while fetuses (FAexp). Also, a significant portion (40–60%) of alcoholics experience emotional blindness.

Short-term effects


The amount of ethanol in the body is typically quantified by blood alcohol content (BAC); weight of ethanol per unit volume of blood. Small doses of ethanol, in general, are stimulant-like and produce euphoria and relaxation; people experiencing these symptoms tend to become talkative and less inhibited, and may exhibit poor judgement. At higher dosages (BAC > 1 gram/liter), ethanol acts as a central nervous system (CNS) depressant, producing at progressively higher dosages, impaired sensory and motor function, slowed cognition, stupefaction, unconsciousness, and possible death. Ethanol is commonly consumed as a recreational substance, especially while socializing, due to its psychoactive effects.

Central nervous system impairment


Alcohol causes generalized CNS depression, is a positive allosteric GABAA modulator and is associated and related with decreased anxiety, decreased social inhibition, sedation, impairment of cognitive, memory, and sensory function, cognitive, memory, motor, and sensory impairment. It slows and impairs cognition and reaction time and the cognitive skills, impairs judgement, interferes with motor function resulting in motor incoordination, numbness, impairs memory formation, and causes sensory impairment.

Binge drinking can cause generalized impairment of neurocognitive function, dizziness, analgesia, amnesia, ataxia (loss of balance, confusion, sedation, slurred speech), general anaesthesia, decreased libido, nausea, vomiting, blackout, spins, stupor, unconsciousness, and hangover.

At very high concentrations, alcohol can cause anterograde amnesia, markedly decreased heart rate, pulmonary aspiration, positional alcohol nystagmus, respiratory depression, shock, coma and death can result due to profound suppression of CNS function alcohol overdose and can finish in consequent dysautonomia.

Gastrointestinal effects


Alcohol can cause nausea and vomiting in sufficiently high amounts (varying by person).

Alcohol stimulates gastric juice production, even when food is not present, and as a result, its consumption stimulates acidic secretions normally intended to digest protein molecules. Consequently, the excess acidity may harm the inner lining of the stomach. The stomach lining is normally protected by a mucosal layer that prevents the stomach from, essentially, digesting itself.

Ingestion of alcohol can initiate systemic pro-inflammatory changes through two intestinal routes: (1) altering intestinal microbiota composition (dysbiosis), which increases lipopolysaccharide (LPS) release, and (2) degrading intestinal mucosal barrier integrity – thus allowing LPS to enter the circulatory system. The major portion of the blood supply to the liver is provided by the portal vein. Therefore, while the liver is continuously fed nutrients from the intestine, it is also exposed to any bacteria and/or bacterial derivatives that breach the intestinal mucosal barrier. Consequently, LPS levels increase in the portal vein, liver and systemic circulation after alcohol intake. Immune cells in the liver respond to LPS with the production of reactive oxygen species, leukotrienes, chemokines and cytokines. These factors promote tissue inflammation and contribute to organ pathology.

Hangover


A hangover is the experience of various unpleasant physiological and psychological effects usually following the consumption of alcohol, such as wine, beer, and liquor. Hangovers can last for several hours or for more than 24 hours. Typical symptoms of a hangover may include headache, drowsiness, concentration problems, dry mouth, dizziness, fatigue, gastrointestinal distress (e.g., nausea, vomiting, diarrhea), absence of hunger, light sensitivity, depression, sweating, hyper-excitability, irritability, and anxiety.

Though many possible remedies and folk cures have been suggested, there is no compelling evidence to suggest that any are effective for preventing or treating hangovers. Avoiding alcohol or drinking in moderation are the most effective ways to avoid a hangover. The socioeconomic consequences of hangovers include workplace absenteeism, impaired job performance, reduced productivity and poor academic achievement. A hangover may also impair performance during potentially dangerous daily activities such as driving a car or operating heavy machinery.

Holiday heart syndrome


Holiday heart syndrome, also known as alcohol-induced atrial arrhythmias, is a syndrome defined by an irregular heartbeat and palpitations associated with high levels of ethanol consumption. Holiday heart syndrome was discovered in 1978 when Philip Ettinger discovered the connection between arrhythmia and alcohol consumption. It received its common name as it is associated with the binge drinking common during the holidays. It is unclear how common this syndrome is. 5-10% of cases of atrial fibrillation may be related to this condition, but it could be as high 63%.

Positional alcohol nystagmus
Positional alcohol nystagmus (PAN) is nystagmus (visible jerkiness in eye movement) produced when the head is placed in a sideways position. PAN occurs when the specific gravity of the membrane space of the semicircular canals in the ear differs from the specific gravity of the fluid in the canals because of the presence of alcohol.

Allergic-like reactions


Ethanol-containing beverages can cause alcohol flush reactions, exacerbations of rhinitis and, more seriously and commonly, bronchoconstriction in patients with a history of asthma, and in some cases, urticarial skin eruptions, and systemic dermatitis. Such reactions can occur within 1–60 minutes of ethanol ingestion, and may be caused by:
 * genetic abnormalities in the metabolism of ethanol, which can cause the ethanol metabolite, acetaldehyde, to accumulate in tissues and trigger the release of histamine, or
 * true allergy reactions to allergens occurring naturally in, or contaminating, alcoholic beverages (particularly wine and beer), and
 * other unknown causes.

Alcohol flush reaction has also been associated with an increased risk of esophageal cancer in those who do drink.

Long-term effects


Due to the long term effects of alcohol abuse, binge drinking is considered to be a major public health issue.

The impact of alcohol on aging is multifaceted. The relationship between alcohol consumption and body weight is the subject of inconclusive studies. Alcoholic lung disease is disease of the lungs caused by excessive alcohol. However, the term 'alcoholic lung disease' is not a generally accepted medical diagnosis.

Alcohol's overall effect on health is uncertain. While some studies suggest moderate consumption might have some benefit, others find any amount increases health risks. This uncertainty is due to conflicting research methods and potential biases, including counting former drinkers as abstainers and the possibility of alcohol industry influence. Because of these issues, experts advise against using alcohol for health reasons. For example, in 2023, the World Health Organization (WHO) stated that there is currently no conclusive evidence from studies that the potential benefits of moderate alcohol consumption for cardiovascular disease and type 2 diabetes outweigh the increased cancer risk associated with these drinking levels for individual consumers.

According to The Lancet, 'four industries (tobacco, unhealthy food, fossil fuel, and alcohol) are responsible for at least a third of global deaths per year'. In 2024, the World Health Organization published a report including these figures.

Alcoholism
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Alcoholism or its medical diagnosis alcohol use disorder refers to alcohol addiction, alcohol dependence, dipsomania, and/or alcohol abuse. It is a major problem and many health problems as well as death can result from excessive alcohol use. Alcohol dependence is linked to a lifespan that is reduced by about 12 years relative to the average person. In 2004, it was estimated that 4% of deaths worldwide were attributable to alcohol use. Deaths from alcohol are split about evenly between acute causes (e.g., overdose, accidents) and chronic conditions. The leading chronic alcohol-related condition associated with death is alcoholic liver disease. Alcohol dependence is also associated with cognitive impairment and organic brain damage. Some researchers have found that even one alcoholic drink a day increases an individual's risk of health problems by 0.4%.

Stigma surrounding alcohol use disorder is particularly strong and different from the stigma attached to other mental illnesses not caused by substances. People with this condition are seen less as truly ill, face greater blame and social rejection, and experience higher structural discrimination risks.

Two or more consecutive alcohol-free days a week have been recommended to improve health and break dependence.

Dry drunk is an expression coined by the founder of Alcoholics Anonymous that describes an alcoholic who no longer drinks but otherwise maintains the same behavior patterns of an alcoholic.

A high-functioning alcoholic (HFA) is a person who maintains jobs and relationships while exhibiting alcoholism.

Many Native Americans in the United States have been harmed by, or become addicted to, drinking alcohol.

Brain damage


While many people associate alcohol's effects with intoxication, the long-term impact of alcohol on the brain can be severe. Binge drinking, or heavy episodic drinking, can lead to alcohol-related brain damage that occurs after a relatively short period of time. This brain damage increases the risk of alcohol-related dementia, and abnormalities in mood and cognitive abilities.

Alcohol can cause Wernicke's encephalopathy and Alcoholic Korsakoff syndrome which frequently occur simultaneously, known as Wernicke–Korsakoff syndrome. Lesions, or brain abnormalities, are typically located in the diencephalon which result in anterograde and retrograde amnesia, or memory loss.

Dementia
Alcohol-related dementia (ARD) is a form of dementia caused by long-term, excessive consumption of alcohol, resulting in neurological damage and impaired cognitive function.

Liver damage


Consuming more than 30 grams of pure alcohol per day over an extended period can significantly increase the risk of developing alcoholic liver disease. During the metabolism of alcohol via the respective dehydrogenases, nicotinamide adenine dinucleotide (NAD) is converted into reduced NAD. Normally, NAD is used to metabolize fats in the liver, and as such alcohol competes with these fats for the use of NAD. Prolonged exposure to alcohol means that fats accumulate in the liver, leading to the term 'fatty liver'. Continued consumption (such as in alcohol use disorder) then leads to cell death in the hepatocytes as the fat stores reduce the function of the cell to the point of death. These cells are then replaced with scar tissue, leading to the condition called cirrhosis.

Cancer


Alcoholic beverages have been classified as carcinogenic by leading health organizations for more than two decades, including the WHO's IARC (Group 1 carcinogens) and the U.S. NTP, raising concerns about the potential cancer risk associated with alcohol consumption.

Drinking alcohol increases the risk for breast cancer. Alcohol is also a major cause for head and neck cancer, especially laryngeal cancer. This risk is even higher when alcohol is used together with tobacco.

Qualitative analysis reveals that the alcohol industry likely misinforms the public about the alcohol-cancer link, similar to the tobacco industry. The alcohol industry influences alcohol policy and health messages, including those for schoolchildren.

Cardiovascular disease
Excessive daily alcohol consumption and binge drinking can cause a higher risk of stroke, coronary artery disease, heart failure, fatal hypertensive disease, and fatal aortic aneurysm.

A 2010 study reviewed a bunch of research on alcohol and heart disease. They found that moderate drinking did not seem to worsen things for people who already had heart problems. But importantly, the researchers did not say that people who do not drink should start in order to improve their heart health. Thus, the safety and potential positive effect of light drinking on the cardiovascular system has not yet been proven. Still alcohol is a major health risk, and even if moderate drinking lowers the risk of some cardiovascular diseases it might increase the risk of others. Therefore starting to drink alcohol in the hope of any benefit is not recommended.

The World Heart Federation (2022) recommends against any alcohol intake for optimal heart health.

It has also been pointed out that the studies suggesting a positive link between red wine consumption and heart health had flawed methodology in the form of comparing two sets of people which were not actually appropriately paired.

Cardiomyopathy


Alcoholic cardiomyopathy (ACM) is a disease in which the long-term consumption of alcohol leads to heart failure. ACM is a type of dilated cardiomyopathy. The heart is unable to pump blood efficiently, leading to heart failure. It can affect other parts of the body if the heart failure is severe. It is most common in males between the ages of 35 and 50.

Hearing loss
Alcohol, classified as an ototoxin (ear toxin), can contribute to hearing loss sometimes referred to as "cocktail deafness" after exposure to loud noises in drinking environments.

Children with fetal alcohol spectrum disorder (FASD) are at an increased risk of having hearing difficulties.

Withdrawal syndrome


Discontinuation of alcohol after extended heavy use and associated tolerance development (resulting in dependence) can result in withdrawal. Alcohol withdrawal can cause confusion, paranoia, anxiety, insomnia, agitation, tremors, fever, nausea, vomiting, autonomic dysfunction, seizures, and hallucinations. In severe cases, death can result.

Delirium tremens is a condition that requires people with a long history of heavy drinking to undertake an alcohol detoxification regimen.

Alcohol is one of the more dangerous drugs to withdraw from. Drugs which help to re-stabilize the glutamate system such as N-acetylcysteine have been proposed for the treatment of addiction to cocaine, nicotine, and alcohol.

Cohort studies have demonstrated that the combination of anticonvulsants and benzodiazepines is more effective than other treatments in reducing alcohol withdrawal scores and shortening the duration of intensive care unit stays.

Nitrous oxide has been shown to be an effective and safe treatment for alcohol withdrawal. The gas therapy reduces the use of highly addictive sedative medications (like benzodiazepines and barbiturates).

Cortisol
Research has looked into the effects of alcohol on the amount of cortisol that is produced in the human body. Continuous consumption of alcohol over an extended period of time has been shown to raise cortisol levels in the body. Cortisol is released during periods of high stress, and can result in the temporary shut down of other physical processes, causing physical damage to the body.

Gout


There is a strong association between gout the consumption of alcohol, and sugar-sweetened beverages, with wine presenting somewhat less of a risk than beer or spirits.

Ketoacidosis
Alcoholic ketoacidosis (AKA) is a specific group of symptoms and metabolic state related to alcohol use. Symptoms often include abdominal pain, vomiting, agitation, a fast respiratory rate, and a specific "fruity" smell. Consciousness is generally normal. Complications may include sudden death.

Mental disorders
Alcohol is a cause of mental disorders. Alcohol may play a role in depression, with up to 10% of male depression cases in some European countries linked to alcohol use.

Alcohol misuse often coincides with mental health conditions. Many individuals struggling with psychiatric disorders also experience problematic drinking behaviors.

Austrian syndrome


Austrian syndrome, also known as Osler's triad, is a medical condition that was named after Robert Austrian in 1957. The presentation of the condition consists of pneumonia, endocarditis, and meningitis, all caused by Streptococcus pneumoniae. It is associated with alcoholism due to hyposplenism (reduced splenic functioning) and can be seen in males between the ages of 40 and 60 years old. Robert Austrian was not the first one to describe the condition, but Richard Heschl (around 1860s) or William Osler were not able to link the signs to the bacteria because microbiology was not yet developed.

The leading cause of Osler's triad (Austrian syndrome) is Streptococcus pneumoniae, which is usually associated with heavy alcohol use.

Polyneuropathy
Alcoholic polyneuropathy is a neurological disorder in which peripheral nerves throughout the body malfunction simultaneously. It is defined by axonal degeneration in neurons of both the sensory and motor systems and initially occurs at the distal ends of the longest axons in the body. This nerve damage causes an individual to experience pain and motor weakness, first in the feet and hands and then progressing centrally. Alcoholic polyneuropathy is caused primarily by chronic alcoholism; however, vitamin deficiencies are also known to contribute to its development.

Pregnant women
Babies exposed to alcohol, benzodiazepines, barbiturates, and some antidepressants (SSRIs) during pregnancy may experience neonatal withdrawal.

The onset of clinical presentation typically appears within 48 to 72 hours of birth but may take up to 8 days.

Other effects


Alcohol consumption is associated with lower sperm concentration, percentage of normal morphology, and semen volume, but not sperm motility.

Alcohol consumption may increase the risk of sleep disorders, including insomnia, restless legs syndrome, and sleep apnea.

Frequent drinking of alcoholic beverages is a major contributing factor in cases of hypertriglyceridemia.

Excess alcohol use is frequently associated with porphyria cutanea tarda (PTC).

Alcohol consumption is a risk factor for Dupuytren's contracture.

The majority of those with aspirin-exacerbated respiratory disease experience respiratory reactions to alcohol.

Alcohol-related crimes
Alcohol use is stereotypically associated with crime, both violent and non-violent. Some crimes are uniquely tied to alcohol, such as public intoxication or underage drinking, while others are simply more likely to occur together with alcohol consumption. Crime perpetrators are much more likely to be intoxicated than crime victims. Many alcohol laws have been passed to criminalize various alcohol-related activities. Underage drinking and drunk driving are the most prevalent alcohol‐specific offenses in the United States and a major problem in many countries worldwide. About one-third of arrests in the United States involve alcohol misuse, and arrests for alcohol-related crimes constitute a high proportion of all arrests made by police in the U.S. and elsewhere. In general, programs aimed at reducing society's consumption of alcohol, including education in schools, are seen as an effective long-term solution. Strategies aiming to reduce alcohol consumption among adult offenders have various estimates of effectiveness. Policing alcohol‐related street disorder and enforcing compliance checks of alcohol‐dispensing businesses has proven successful in reducing public perception of and fear of criminal activities.

In the early 2000s, the monetary cost of alcohol-related crime in the United States alone has been estimated at over $205 billion, twice the economic cost of all other drug-related crimes. In a similar period in the United Kingdom, the cost of crime and its antisocial effects was estimated at £7.3 billion. Another estimate for the UK for yearly cost of alcohol-related crime suggested double that estimate, at between £8 and 13 billion. Risky patterns of drinking are particularly problematic in and around Russia, Mexico and some parts of Africa. Alcohol is more commonly associated with both violent and non-violent crime than are drugs like marijuana.

Passive drinking, like passive smoking, refers to the damage done to others as a result of drinking alcoholic beverages. These include the unborn fetus and children of parents who drink excessively, drunk drivers, accidents, domestic violence and alcohol-related sexual assaults

Public-order crimes
Public-order crimes caused by drinking include drunk driving, domestic violence, and alcohol-related sexual assaults.

Automobile accidents


A 2002 study found 41% of people fatally injured in traffic accidents were in alcohol-related crashes. Misuse of alcohol is associated with more than 40% of deaths that occur in automobile accidents every year. The risk of a fatal car accident increases exponentially with the level of alcohol in the driver's blood.

Most countries have passed laws prohibiting driving a motor vehicle while impaired by alcohol. In the U.S., these crimes are generally referred to as driving under the influence (DUI), although there are many naming variations among jurisdictions, such as driving while intoxicated (DWI). With alcohol consumption, a drunk driver's level of intoxication is typically determined by a measurement of blood alcohol content or BAC; but this can also be expressed as a breath test measurement, often referred to as a BrAC. A BAC or BrAC measurement in excess of the specific threshold level, such as 0.08% in the U.S., defines the criminal offense with no need to prove impairment. In some jurisdictions, there is an aggravated category of the offense at a higher BAC level, such as 0.12%, 0.15% or 0.25%. In many jurisdictions, police officers can conduct field tests of suspects to look for signs of intoxication.

Negligence


Negligence in alcohol consumption can have a ripple effect on environmentally responsible behavior. Examples:
 * Consuming alcoholic beverages, which increases urine production and reduces social inhibitions, can lead to public urination. Public urination is illegal in most areas.
 * Improper disposal of alcohol bottles is a common problem. Many are not recycled or left behind in public spaces. Discarded alcoholic beverage containers, especially broken glass shards that are difficult to remove, does not only create an eyesore but may also cause flat tires for cyclists, injure wildlife or kids.
 * Alcohol consumption can contribute to nighttime noise pollution, especially through loud music played by intoxicated individuals. This disrupts sleep and relaxation for nearby residents, impacting health and productivity. Municipal noise ordinances often establish quiet hours and penalties for violations.
 * People under the influence may forget to extinguish outdoor fireplaces, which may create a fire hazard since unchecked fires can escalate into wildfires.
 * Drunk cyclists can only be charged if they ride dangerously, cause a crash, or behave disruptively. However, cycling under the influence increases the risk of severe injury, hospital resource use, and even death, according to a study highlighting the importance of safe cycling practices.

Public drunkenness


Public drunkenness or intoxication is a common problem in many jurisdictions. Public intoxication laws vary widely by jurisdiction, but include public nuisance laws, open-container laws, and prohibitions on drinking alcohol in public or certain areas. The offenders are often lower class individuals and this crime has a very high recidivism rate, with numerous instances of repeated instances of the arrest, jail, release without treatment cycle. The high number of arrests for public drunkenness often reflects rearrests of the same offenders.

Sexual assaults
Rape is any sexual activity that occurs without the freely given consent of one of the parties involved. This includes alcohol-facilitated sexual assault which is considered rape in most if not all jurisdictions, or non-consensual condom removal which is criminalized in some countries (see the map below).

A 2008 study found that rapists typically consumed relatively high amounts of alcohol and infrequently used condoms during assaults, which was linked to a significant increase in STI transmission. This also increase the risk of pregnancy from rape for female victims. Some people turn to drugs or alcohol to cope with emotional trauma after a rape; use of these during pregnancy can harm the fetus.

Alcohol-facilitated sexual assault


One of the most common date rape drugs is alcohol,  administered either surreptitiously or consumed voluntarily, rendering the victim unable to make informed decisions or give consent. The perpetrator then facilitates sexual assault or rape, a crime known as alcohol- or drug-facilitated sexual assault (DFSA). However, sex with an unconscious victim is considered rape in most if not all jurisdictions, and some assailants have committed "rapes of convenience" whereby they have assaulted a victim after he or she had become unconscious from drinking too much. The risk of individuals either experiencing or perpetrating sexual violence and risky sexual behavior increases with alcohol abuse, and by the consumption of caffeinated alcoholic drinks.

Non-consensual condom removal


Non-consensual condom removal, or "stealthing", is the practice of a person removing a condom during sexual intercourse without consent, when their sex partner has only consented to condom-protected sex. Purposefully damaging a condom before or during intercourse may also be referred to as stealthing, regardless of who damaged the condom.

Consuming alcohol can be risky in sexual situations. It can impair judgment and make it difficult for both people to give or receive informed sexual consent. However, a history of sexual aggression and alcohol intoxication are factors associated with an increased risk of men employing non-consensual condom removal and engaging in sexually aggressive behavior with female partners.

Wartime sexual violence
The use of alcohol is a documented factor in wartime sexual violence.

For example, rape during the liberation of Serbia was committed by Soviet Red Army soldiers against women during their advance to Berlin in late 1944 and early 1945 during World War II. Serbian journalist Vuk Perišić said about the rapes: "The rapes were extremely brutal, under the influence of alcohol and usually by a group of soldiers. The Soviet soldiers did not pay attention to the fact that Serbia was their ally, and there is no doubt that the Soviet high command tacitly approved the rape."

While there was not a codified international law specifically prohibiting rape during World War II, customary international law principles already existed that condemned violence against civilians. These principles formed the basis for the development of more explicit laws after the war, including the Nuremberg Principles established in 1950.

Violent crime


The World Health Organization has noted that out of social problems created by the harmful use of alcohol, "crime and violence related to alcohol consumption" are likely the most significant issue. In the United States, 15% of robberies, 63% of intimate partner violence incidents, 37% of sexual assaults, 45–46% of physical assaults and 40–45% of homicides (murders) involved use of alcohol. A 1983 study for the United States found that 54% of violent crime perpetrators, arrested in that country, had been consuming alcohol before their offenses. In 2002, it was estimated that 1 million violent crimes in the U.S. were related to alcohol use. More than 43% of violent encounters with police involve alcohol. Alcohol is implicated in more than two-thirds of cases of intimate partner violence. Studies also suggest there may be links between alcohol abuse and child abuse. In the United Kingdom, in 2015/2016, 39% of those involved in violent crimes were under alcohol influence. A significant portion, 40%, of homicide victims tested positive for alcohol in the US. International studies are similar, with an estimate that 63% of violent crimes worldwide involves the use of alcohol.

The relation between alcohol and violence is not yet fully understood, as its impact on different individuals varies. Studies and theories of alcohol abuse suggest, among others, that use of alcohol likely reduces the offender's perception and awareness of consequences of their actions. Heavy drinking is associated with vulnerability to injury, marital discord, and domestic violence. Moderate drinkers are more frequently engaged in intimate violence than are light drinkers and abstainers, however generally it is heavy and/or binge drinkers who are involved in the most chronic and serious forms of aggression. Research found that factors that increase the likelihood of alcohol‐related violence include difficult temperament, hyperactivity, hostile beliefs, history of family violence, poor school performance, delinquent peers, criminogenic beliefs about alcohol's effects, impulsivity, and antisocial personality disorder. The odds, frequency, and severity of physical attacks are all positively correlated with alcohol use. In turn, violence decreases after behavioral marital alcoholism treatment.

Methanol laced alcohol


Outbreaks of methanol poisoning have occurred when methanol is used to lace moonshine (bootleg liquor). This is commonly done to bulk up the original product to gain profit. Because of its similarities in both appearance and odor to ethanol (the alcohol in beverages), it is difficult to differentiate between the two.

Methanol is a toxic alcohol. If as little as 10 mL of pure methanol is ingested, for example, it can break down into formic acid, which can cause permanent blindness by destruction of the optic nerve, and 30 mL is potentially fatal, although the median lethal dose is typically 100 mL (3.4 fl oz) (i.e. 1–2 mL/kg body weight of pure methanol ). Reference dose for methanol is 2.0 mg/kg/day. Toxic effects take hours to start, and effective antidotes can often prevent permanent damage.

India has a thriving moonshine industry, and methanol-tainted batches have killed over 2,000 people in the last 3 decades.

Alternative routes of administration
Alternative methods of alcohol administration like alcohol enema, alcohol inhalation, vodka eyeballing, or using alcohol powder (which can be added to water to make an alcoholic beverage, or inhaled with a nebulizer), all carry significant health risks.

Binge drinking


Binge drinking is a style of drinking that is popular in several countries worldwide, and overlaps somewhat with social drinking since it is often done in groups. The degree of intoxication however, varies between and within various cultures that engage in this practice. A binge on alcohol can occur over hours, last up to several days, or in the event of extended abuse, even weeks. Due to the long term effects of alcohol abuse, binge drinking is considered to be a major public health issue.

Binge drinking is more common in males, during adolescence and young adulthood. Heavy regular binge drinking is associated with adverse effects on neurologic, cardiac, gastrointestinal, hematologic, immune, and musculoskeletal organ systems as well as increasing the risk of alcohol induced psychiatric disorders. A US-based review of the literature found that up to one-third of adolescents binge-drink, with 6% reaching the threshold of having an alcohol-related substance use disorder. Approximately one in 25 women binge-drinks during pregnancy, which can lead to fetal alcohol syndrome and fetal alcohol spectrum disorders. Binge drinking during adolescence is associated with traffic accidents and other types of accidents, violent behavior as well as suicide. The more often a child or adolescent binge drinks and the younger they are the more likely that they will develop an alcohol use disorder including alcoholism. A large number of adolescents who binge-drink also consume other psychotropic substances.

Emotional issues
In emotional self-regulation, some people turn to drugs such as alcohol. Drug use, an example of response modulation, can be used to alter emotion-associated physiological responses. For example, alcohol can produce sedative and anxiolytic effects. A 2013 study found that immature defense mechanisms are linked to placing a higher value on junk food, alcohol, and television.

There is a two-way street between loneliness and drinking. People who drink more than once a week tend to feel lonelier, according to a study on Japanese workers during the COVID-19 pandemic. On the other hand, feelings of loneliness can also lead people to drink more, as shown in a separate study. Loneliness is a major risk factor for depression and alcoholism.

Hurtful communication
Alcohol may cause hurtful communication.

Drunk dialing
Drunk dialing refers to an intoxicated person making phone calls that they would not likely make if sober, often a lonely individual calling former or current love interests.

A 2021 study, that examined the relationship between drunk texting and emotional dysregulation, found a positive correlation. The findings suggest that interventions targeting emotional regulation skills may be beneficial.

In vino veritas
In vino veritas is a Latin phrase that means in wine, there is truth, suggesting a person under the influence of alcohol is more likely to speak their hidden thoughts and desires.

Risky sexual behavior
Some studies have made a connection between hookup culture and substance use. Most students said that their hookups occurred after drinking alcohol. Frietas stated that in her study, the relationships between drinking and the party scene and between alcohol and hookup culture were "impossible to miss."

Studies suggest that the degree of alcoholic intoxication in young people directly correlates with the level of risky behavior, such as engaging in multiple sex partners.

In 2018, the first study of its kind, found that alcohol and caffeinated energy drinks is linked with casual, risky sex among college-age adults.

Sexually transmitted infections and unintended pregnancy


Alcohol intoxication is associated with an increased risk that people will become involved in risky sexual behaviors, such as unprotected sex. Both men, and women, reported higher intentions to avoid using a condom when they were intoxicated by alcohol.

Coitus interruptus, also known as withdrawal, pulling out or the pull-out method, is a method of birth control during penetrative sexual intercourse, whereby the penis is withdrawn from a vagina or anus prior to ejaculation so that the ejaculate (semen) may be directed away in an effort to avoid insemination. Coitus interruptus carries a risk of STIs and unintended pregnancy. This risk is especially high during alcohol intoxication because lowered sexual inhibition can make it difficult to withdraw in time.

Women with unintended pregnancies are more likely to smoke tobacco, drink alcohol during pregnancy, and binge drink during pregnancy, which results in poorer health outcomes. (See also: fetal alcohol spectrum disorder)

Societal damage


Alcohol causes a plethora of detrimental effects in society. A 2023 systematic review estimated the societal costs of alcohol use to be around 2.6% of the GDP. Many emergency room visits involve alcohol use. Alcohol availability and consumption rates and alcohol rates are positively associated with nuisance, loitering, panhandling, and disorderly conduct in public space.

A 2011 study challenged the perception of heroin as the more dangerous substance. The research suggests, when considering the wider social, physical, and financial costs, alcohol may be more harmful.

Individuals who engage with or share alcohol-related content on social networking services tend to exhibit higher levels of alcohol use and related issues. Overwork is linked to an increased risk of unhealthy alcohol consumption. Also, unemployment can heighten the risk of alcohol consumption and smoking. As many as 15% of employees show problematic alcohol-related behaviors in the workplace, such as drinking before going to work or even drinking on the job.

College
Many students attending colleges, universities, and other higher education institutions consume alcoholic beverages. The laws and social culture around this practice vary by country and institution type, and within an institution, some students may drink heavily whereas others may not drink at all. In the United States, drinking tends to be particularly associated with fraternities.

Alcohol abuse among college students refers to unhealthy alcohol drinking behaviors by college and university students. While the legal drinking age varies by country, the high amount of underage students that consume alcohol has presented many problems and consequences for universities. The causes of alcohol abuse tend to be peer pressure, fraternity or sorority involvement, and stress. College students who abuse alcohol can suffer from health concerns, poor academic performance or legal consequences. Prevention and treatment include campus counseling, stronger enforcement of underage drinking or changing the campus culture.

Recent research indicates that the abundance of alcohol retailers and the availability of inexpensive alcoholic beverages are linked to heavy alcohol consumption among college students.

Poverty
Alcohol consumption can contribute to secondary poverty (where people fall back into poverty after escaping it). The Bureau of Labor Statistics found that "the average American consumer dedicates 1 percent of all their spending to alcohol".

Unsustainable tourism
Some popular tourist destinations, are cracking down on the impacts of tourism from excessive drinking. In an effort to promote a more sustainable tourism industry, these locations are implementing new regulations to curb binge drinking. This includes Llucmajor, Palma, Calvia (Magaluf) in Majorca and Sant Antoni in Ibiza, where late-night sales of alcohol will be banned. This comes after years of issues with rowdy tourists and the negative impacts it has on local residents.

Suicide
Most people are under the influence of sedative-hypnotic drugs (such as alcohol or benzodiazepines) when they die by suicide, with alcoholism present in between 15% and 61% of cases. Countries that have higher rates of alcohol use and a greater density of bars generally also have higher rates of suicide. About 2.2–3.4% of those who have been treated for alcoholism at some point in their life die by suicide. Alcoholics who attempt suicide are usually male, older, and have tried to take their own lives in the past. In adolescents who misuse alcohol, neurological and psychological dysfunctions may contribute to the increased risk of suicide.

Covid
A 2023 study suggests a link between alcohol consumption and worse COVID-19 outcomes. Researchers analyzed data from over 1.6 million people and found that any level of alcohol consumption increased the risk of severe illness, intensive care unit admission, and needing ventilation compared to non-drinkers. Even a history of drinking was associated with a higher risk of severe COVID-19. These findings suggest that avoiding alcohol altogether might be beneficial during the pandemic.

Diabetes
See the insulin section.

Heptatitis
Alcohol consumption can be especially dangerous for those with pre-existing liver damage from hepatitis B or C. Even relatively low amounts of alcohol can be life-threatening in these cases, so a strict adherence to abstinence is highly recommended.

Hitamine intolerance
Alcohol may release histamine in individuals with histamine intolerance.

Mental disorders


Mental disorders can be a significant risk factor for alcohol abuse.

Alcohol abuse, alcohol dependence, and alcoholism are comorbid with anxiety disorders. With dual diagnosis, the initial symptoms of mental illness tend to appear before those of substance abuse. Individuals with common mental health conditions, such as depression, anxiety, or phobias, are twice as likely to also report having an alcohol use disorder, compared to those without these mental health challenges. Alcohol is a major risk factor for self-harm. Individuals with anxiety disorders who self-medicate with drugs or alcohol may also have an increased likelihood of suicidal ideation.

Peptic ulcer disease
In patients who have a peptic ulcer disease (PUD), the mucosal layer is broken down by ethanol. PUD is commonly associated with the bacteria Helicobacter pylori, which secretes a toxin that weakens the mucosal wall, allowing acid and protein enzymes to penetrate the weakened barrier. Because alcohol stimulates the stomach to secrete acid, a person with PUD should avoid drinking alcohol on an empty stomach. Drinking alcohol causes more acid release, which further damages the already-weakened stomach wall. Complications of this disease could include a burning pain in the abdomen, bloating and in severe cases, the presence of dark black stools indicate internal bleeding. A person who drinks alcohol regularly is strongly advised to reduce their intake to prevent PUD aggravation.

Alcohol induced dose dumping (AIDD)
Alcohol-induced dose dumping (AIDD) is by definition an unintended rapid release of large amounts of a given drug, when administered through a modified-release dosage while co-ingesting ethanol. This is considered a pharmaceutical disadvantage due to the high risk of causing drug-induced toxicity by increasing the absorption and serum concentration above the therapeutic window of the drug. The best way to prevent this interaction is by avoiding the co-ingestion of both substances or using specific controlled-release formulations that are resistant to AIDD.

Drugs
Alcohol can intensify the sedation caused by antipsychotics, and certain antidepressants.

Alcohol combined with cannabis (not to be confused with tincture of cannabis which contains minute quantities of alcohol) — known as cross-fading and may easily cause spins in people who are drunk and smoke potent cannabis; Ethanol increases plasma tetrahydrocannabinol levels, which suggests that ethanol may increase the absorption of tetrahydrocannabinol.

TOMSO is a lesser-known psychedelic drug and a substituted amphetamine. TOMSO was first synthesized by Alexander Shulgin. According to Shulgin's book PiHKAL, TOMSO is inactive on its own and requires consumption of alcohol to become active.

Hypnotics/sedatives


Alcohol can intensify the sedation caused by hypnotics/sedatives such as barbiturates, benzodiazepines, sedative antihistamines, opioids, nonbenzodiazepines/Z-drugs (such as zolpidem and zopiclone).

Disulfiram
Disulfiram inhibits the enzyme acetaldehyde dehydrogenase, which in turn results in buildup of acetaldehyde, a toxic metabolite of ethanol with unpleasant effects. The medication or drug is commonly used to treat alcohol use disorder, and results in immediate hangover-like symptoms upon consumption of alcohol, this effect is widely known as disulfiram effect.

Metronidazole
Metronidazole is an antibacterial agent that kills bacteria by damaging cellular DNA and hence cellular function. Metronidazole is usually given to people who have diarrhea caused by Clostridium difficile bacteria. Patients who are taking metronidazole are sometimes advised to avoid alcohol, even after 1 hour following the last dose. Although older data suggested a possible disulfiram-like effect of metronidazole, newer data has challenged this and suggests it does not actually have this effect.

Insulin
Alcohol consumption can cause hypoglycemia in diabetics on certain medications, such as insulin or sulfonylurea, by blocking gluconeogenesis.

NSAIDs
The concomitant use of NSAIDs with alcohol and/or tobacco products significantly increases the already elevated risk of peptic ulcers during NSAID therapy.

The risk of stomach bleeding is still increased when aspirin is taken with alcohol or warfarin.

Stimulants


Controlled animal and human studies showed that caffeine (energy drinks) in combination with alcohol increased the craving for more alcohol more strongly than alcohol alone. These findings correspond to epidemiological data that people who consume energy drinks generally showed an increased tendency to take alcohol and other substances.

Ethanol interacts with cocaine in vivo to produce cocaethylene, another psychoactive substance which may be substantially more cardiotoxic than either cocaine or alcohol by themselves.

Ethylphenidate formation appears to be more common when large quantities of methylphenidate and alcohol are consumed at the same time, such as in non-medical use or overdose scenarios. However, only a small percent of the consumed methylphenidate is converted to ethylphenidate.

While nicotinis mimic the name of classic cocktails like the appletini (their name deriving from "martini"), combining nicotine with alcohol is a bad idea. Tobacco and nicotine actually heighten cravings for alcohol, making this a risky mix.

Methanol and ethylene glycol
The rate-limiting steps for the elimination of ethanol are in common with certain other substances. As a result, the blood alcohol concentration can be used to modify the rate of metabolism of toxic alcohols, such as methanol and ethylene glycol. Methanol itself is not highly toxic, but its metabolites formaldehyde and formic acid are; therefore, to reduce the rate of production and concentration of these harmful metabolites, ethanol can be ingested. Ethylene glycol poisoning can be treated in the same way.

Warfarin
Excessive use of alcohol is also known to affect the metabolism of warfarin and can elevate the INR, and thus increase the risk of bleeding. The U.S. Food and Drug Administration (FDA) product insert on warfarin states that alcohol should be avoided. The Cleveland Clinic suggests that when taking warfarin one should not drink more than "one beer, 6 oz of wine, or one shot of alcohol per day".

Isoniazid
Levels of liver enzymes in the bloodstream should be frequently checked in daily alcohol drinkers, pregnant women, IV drug users, people over 35, and those who have chronic liver disease, severe kidney dysfunction, peripheral neuropathy, or HIV infection since they are more likely to develop hepatitis from INH.

Pharmacology
The pharmacology of ethanol involves both pharmacodynamics (how it affects the body) and pharmacokinetics (how the body processes it). In the body, ethanol primarily affects the central nervous system, acting as a depressant and causing sedation, relaxation, and decreased anxiety. The exact mechanism remains elusive, but ethanol has been shown to affect ligand-gated ion channels, particularly the GABAA receptor.

After oral ingestion, ethanol is absorbed via the stomach and intestines into the bloodstream. Ethanol is highly water-soluble and diffuses passively throughout the entire body, including the brain. Soon after ingestion, it begins to be metabolized, 90% or more by the liver. One standard drink is sufficient to almost completely saturate the liver's capacity to metabolize alcohol. The main metabolite is acetaldehyde, a toxic carcinogen. Acetaldehyde is then further metabolized into ionic acetate by the enzyme aldehyde dehydrogenase (ALDH). Acetate is not carcinogenic and has low toxicity, but has been implicated in causing hangovers. Acetate is further broken down into carbon dioxide and water and eventually eliminated from the body through urine and breath. 5 to 10% of ethanol is excreted unchanged in the breath, urine, and sweat.

Alcohol also direct affects a number of other neurotransmitter systems including those of glutamate, glycine, acetylcholine, and serotonin. The pleasurable effects of alcohol ingestion are the result of increased levels of dopamine and endogenous opioids in the reward pathways of the brain.

Safety


Symptoms of ethanol overdose may include nausea, vomiting, CNS depression, coma, acute respiratory failure, or death. Levels of even less than 0.1% can cause intoxication, with unconsciousness often occurring at 0.3–0.4%. Death from ethanol consumption is possible when blood alcohol levels reach 0.4%. A blood level of 0.5% or more is commonly fatal. The oral median lethal dose (LD50) of ethanol in rats is 5,628 mg/kg. Directly translated to human beings, this would mean that if a person who weighs 70 kg drank a 500 mL glass of pure ethanol, they would theoretically have a 50% risk of dying. The highest blood alcohol level ever recorded, in which the subject survived, is 1.41%.

The DEA has claimed illegal drugs are more deadly than alcohol, citing CDC data from 2000 showing similar death counts despite alcohol's wider use. However, this comparison is disputed; a JAMA article reported alcohol-related deaths in 2000 as 85,000, significantly higher than the DEA's figure of 18,539.

Toxicity
Ethanol is classified as a hepatotoxin, neurotoxin, and ototoxin, which has acute toxic effects on the liver, the nervous system, and the ears, respectively. However, ethanol's acute effects on these organs are usually reversible. This means that even with a single episode of heavy drinking, the body can typically repair itself from the initial damage. Methanol laced alcohol on the other hand can cause blindness even in small quantities.

Chemistry
Ethanol is also known chemically as alcohol, ethyl alcohol, or drinking alcohol. It is a simple alcohol with a molecular formula of C2H6O and a molecular weight of 46.0684 g/mol. The molecular formula of ethanol may also be written as CH3−CH2−OH or as C2H5−OH. The latter can also be thought of as an ethyl group linked to a hydroxyl (alcohol) group and can be abbreviated as EtOH. Ethanol is a volatile, flammable, colorless liquid with a slight characteristic odor. Aside from its use as a psychoactive and recreational substance, ethanol is also commonly used as an antiseptic and disinfectant, a chemical and medicinal solvent, and a fuel.

Production
Ethanol is produced naturally as a byproduct of the metabolic processes of yeast and hence is present in any yeast habitat, including even endogenously in humans, but it does not cause raised blood alcohol content as seen in the rare medical condition auto-brewery syndrome (ABS). It is manufactured through hydration of ethylene or by brewing via fermentation of sugars with yeast (most commonly Saccharomyces cerevisiae). The sugars are commonly obtained from sources like steeped cereal grains (e.g., barley), grape juice, and sugarcane products (e.g., molasses, sugarcane juice). Ethanol–water mixture which can be further purified via distillation.

Homebrewing


Homebrewing is the brewing of beer  or other alcoholic beverages on a small scale for personal, non-commercial purposes. Supplies, such as kits and fermentation tanks, can be purchased locally at specialty stores or online. Beer was brewed domestically for thousands of years before its commercial production, although its legality has varied according to local regulation. Homebrewing is closely related to the hobby of home distillation, the production of alcoholic spirits for personal consumption; however home distillation is generally more tightly regulated.

Moonshine
Although methanol is not produced in toxic amounts by fermentation of sugars from grain starches, it is a major occurrence in fruit spirits. However, in modern times, reducing methanol with the absorption of a molecular sieve is a practical method for production.

Analogues


Ethanol has a variety of analogues, many of which have similar actions and effects. In chemistry, "alcohol" can encompass other mind-altering alcohols besides the kind we drink. Some examples include synthetic drugs like ethchlorvynol and methylpentynol, once used in medicine. Also, ethanol is colloquially referred to as "alcohol" because it is the most prevalent alcohol in alcoholic beverages. But technically all alcoholic beverages contain several types of psychoactive alcohols, that are categorized as primary, secondary, or tertiary. Primary, and secondary alcohols, are oxidized to aldehydes, and ketones, respectively, while tertiary alcohols are generally resistant to oxidation. Ethanol is a primary alcohol that has unpleasant actions in the body, many of which are mediated by its toxic metabolite acetaldehyde. Less prevalent alcohols found in alcoholic beverages, are secondary, and tertiary alcohols. For example, the tertiary alcohol 2M2B which is up to 50 times more potent than ethanol and found in trace quantities in alcoholic beverages, has been synthesized and used as a designer drug. Alcoholic beverages are sometimes laced with toxic alcohols, such as methanol (the simplest alcohol) and isopropyl alcohol. A mild, brief exposure to isopropyl alcohol (which is only moderately more toxic than ethanol) is unlikely to cause any serious harm. But many methanol poisoning incidents have occurred through history, since methanol is lethal even in small quantities, as little as 10–15 milliliters (2–3 teaspoons). Ethanol is used to treat methanol and ethylene glycol toxicity.

The Lucas test differentiates between primary, secondary, and tertiary alcohols.

Consumption recommendations


The recommended maximum intake (or ) of alcohol varies from no intake, to daily, weekly, or daily/weekly guidelines provided by health agencies of governments. The World Health Organization published a statement in The Lancet Public Health in April 2023 that "there is no safe amount that does not affect health".

According to the U.S. Department of Agriculture, based on NHANES 2013–2014 surveys, women in the US ages 20 and up consume on average 6.8 grams/day and men consume on average 15.5 grams/day. A March 2023 review found light-moderate daily drinking not significantly associated with increased mortality rate, but higher intake raises risk, with women affected at lower levels than men. However, according to a 2024 systematic review and meta-analysis, even at 20 g/day (1 large beer), the risk of developing an alcohol use disorder (AUD) is nearly 3 times higher than non-drinkers, and the risk of dying from an AUD is about 2 times higher than non-drinkers.

Drinking culture


Ethanol is typically consumed as a recreational substance by mouth in the form of alcoholic beverages such as beer, wine, and spirits. It is commonly used in social settings due to its capacity to enhance sociability.

Drinking alcohol is generally socially acceptable and is legal in most countries, unlike with many other recreational substances. Many students attending colleges, universities, and other higher education institutions consume alcoholic beverages. However, there are often restrictions on alcohol sale and use, for instance a minimum age for drinking and laws against public drinking and drinking and driving. A 2024 meta-analysis found that alcohol consumption increased on average each year, with the most significant rise occurring between the ages of 12 and 13. Drinking peaked around 22 years old, then began to decline at 24.

Alcohol holds considerable societal and cultural significance, playing a role in social interactions across much of the world. Drinking establishments, such as bars and nightclubs, revolve primarily around the sale and consumption of alcoholic beverages, and parties, festivals, and social gatherings commonly involve alcohol consumption. Alcohol is related to various societal problems, including drunk driving, accidental injuries, sexual assaults, domestic abuse, and violent crime. Alcohol remains illegal for sale and consumption in a number of countries, mainly in the Middle East.

Research on the societal benefits of alcohol is rare, but a 2017 study suggested there it was beneficial. Alcohol is often used as a social lubricant; it increases occurrences of Duchenne smiling, talking, and social bonding, even when participants are unaware of their alcohol consumption or lack thereof. In a study of the UK, regular drinking was correlated with happiness, feeling that life was worthwhile, and life satisfaction. According to a causal path analysis the cause was vice versa; alcohol consumption was not the cause, but rather that the life satisfaction resulted in greater happiness and an inclination to visit pubs and develop a regular drinking venue. City centre bars were distinguished by their focus on maximizing alcohol sales. Community pubs had less variation in visible group sizes and longer, more focused conversations than those in city centre bars. Drinking regularly at a community pub led to higher trust in others and better networking with the local community, compared to non-drinkers and city centre bar drinkers.

Religion


The relationship between religion and alcohol exhibits variations across cultures, geographical areas, and religious denominations. Some religions emphasize moderation and responsible use as a means of honoring the divine gift of life, while others impose outright bans on alcohol as a means of honoring the divine gift of life. Moreover, within the same religious tradition, there are many adherents that may interpret and practice their faith's teachings on alcohol in diverse ways. Hence, a wide range of factors, such as religious affiliation, levels of religiosity, cultural traditions, family influences, and peer networks, collectively influence the dynamics of this relationship.

The levels of alcohol use in spiritual context can be broken down into:
 * Prohibition: Some religions, including Islam prohibit alcohol consumption.
 * Symbolic use: In some Christian denominations, the sacramental wine is alcoholic, however, only a sip is taken, and it does not raise the blood alcohol content, and other denominations are using nonalcoholic wine. See also Libation.
 * Discourage consumption: Hinduism does not have a central authority which is followed by all Hindus, though religious texts generally discourage the use or consumption of alcohol.
 * Inebriating spiritual use: See the spiritual section.
 * Recreational use: Recreational drug use of alcohol in moderation to celebrate joy, is allowed in some religions.
 * Christian views on alcohol are varied. For example, in the mid-19th century, some Protestant Christians moved from a position of allowing moderate use of alcohol (sometimes called moderationism) to either deciding that not imbibing was wisest in the present circumstances (abstentionism) or prohibiting all ordinary consumption of alcohol because it was believed to be a sin (prohibitionism).


 * During the Jewish holiday of Purim, Jews are obligated to drink (especially Kosher wine) until their judgmental abilities become impaired according to the Book of Esther.  However, Purim has more of a national than a religious character.

Legal status


Alcohol consumption is fully legal and available in most countries of the world. Home made alcoholic beverages with low alcohol content like wine, and beer is also legal in most countries, but distilling moonshine outside of a registered distillery remains illegal in most of them.

Some majority-Muslim countries, such as Saudi Arabia, Kuwait, Pakistan, Iran and Libya prohibit the production, sale, and consumption of alcoholic beverages because they are forbidden by Islam. Laws banning alcohol consumption are found in some Indian states as well as some Native American reservations in the U.S.

In addition, there are regulations on alcohol sales and use in many countries throughout the world. For instance, the majority of countries have a minimum legal drinking age to purchase or consume alcoholic beverages, although there are often exceptions such as underage consumption of small amounts of alcohol with parental supervision. Also, some countries have bans on public intoxication. Drinking while driving or intoxicated driving is frequently outlawed and it may be illegal to have an open container of alcohol or liquor bottle in an automobile, bus or aircraft.

In Iran, consumption of alcohol (one glass) is punished by 80 lashes, but repeated offences may lead to death penalty, although rarely exercised. In 2012, two men were sentenced to death after a third offense in Khorasan.

Alcohol packaging warning messages


Alcohol packaging warning messages (alcohol warning labels, AWLs ) are warning messages that appear on the packaging of alcoholic drinks concerning their health effects.

A World Health Organization report, published in 2017, stated: "Alcohol product labelling could be considered as a component of a comprehensive public health strategy to reduce alcohol-related harm. Adding health labels to alcohol containers is an important first step in raising awareness and has a longer-term utility in helping to establish a social understanding of the harmful use of alcohol."

Criticism of the alcohol industry


A 2019 survey conducted by the American Institute for Cancer Research (AICR) showed that only 45% of Americans were aware of the associated risk of cancer due to alcohol consumption, up from 39% in 2017. The AICR believes that alcohol-related advertisements about the healthy cardiovascular benefits of modest alcohol overshadow messages about the increased cancer risks.

Drinking alcoholic beverages increase the risk for breast cancer. Several studies indicate that the use of marketing by the alcohol industry to associate their products with breast cancer awareness campaigns, known as pinkwashing, is misleading and potentially harmful.

The alcohol industries have marketed products directly to the LGBT+ community. In 2010, of the sampled parades that listed sponsors, 61% of the prides were sponsored by the alcohol industry. A study found that alcohol consumption within LGBTQ+ communities presents a challenge for health promotion efforts. The positive association with alcohol within these communities makes it harder to reduce alcohol-related health issues.

Standard drink
A standard drink is a measure of alcohol consumption representing a fixed amount of pure ethanol, used in relation to recommendations about alcohol consumption and its relative risks to health. The size of a standard drink varies from 8g to 20g across countries, but 10g alcohol (12.7 millilitres) is used in the World Health Organization (WHO) Alcohol Use Disorders Identification Test (AUDIT)'s questionnaire form example, and has been adopted by more countries than any other amount.

Sober curious


Sober curious is a cultural movement and lifestyle of consuming no or limited alcohol that started in the late 2010s. It differs from traditional abstinence in that it is not founded on asceticism, religious condemnation of alcohol or previous alcohol abuse, but motivated by a curiosity of a sober lifestyle. Markets have reacted by offering a wider selection of non-alcoholic beverages.

Sober curiosity is often defined as having the option to question or change one's drinking habits, for mental or physical health reasons. It may be practised in many ways, ranging from complete abstinence to more thought about when and how much is consumed.

Since the onset of the COVID-19 pandemic, more people in Europe have reduced their alcohol consumption.

History
The consumption of alcohol has a long human history. Beginning with the Gin Craze, excessive drinking and drunkenness developed into a major problem for public health. Prohibition marked a turning point, as alcohol transitioned from widely accepted to strictly controlled, recognized as a dangerous drug. After its repeal, societal views softened dramatically. Alcohol consumption became normalized, and for many years, the public remained largely unaware of the well-established dangers, including its carcinogenic and teratogenic properties. However, a recent shift has brought these risks back to light. The WHO's 2023 declaration that no amount of alcohol consumption is entirely safe served as a wake-up call.

Ancient World
Since antiquity, prior to the development of modern agents, alcohol was used as a general anaesthetic.

Beer is one of the earliest known ingredients for wound healing. A medical prescription from Mesopotamia describes a method for healing wounds: "Pound together fur-turpentine, pine-turpentine, tamarisk, daisy, flour of inninnu strain; mix in milk and beer in a small copper pan; spread on skin; bind on him, and he shall recover."

Late Middle Ages
Alcohol has been used as an antiseptic as early as 1363 with evidence to support its use becoming available in the late 1800s.

Early modern period


The popular story dates the etymology of the term Dutch courage to English soldiers fighting in the Anglo-Dutch Wars (1652–1674) and perhaps as early as the Thirty Years' War (1618–1648). One version states that jenever (or Dutch gin) was used by English soldiers for its calming effects before battle, and for its purported warming properties on the body in cold weather. Another version has it that English soldiers noted the bravery-inducing effects of jenever on Dutch soldiers.

The Gin Craze was a period in the first half of the 18th century when the consumption of gin increased rapidly in Great Britain, especially in London. By 1743, England was drinking 2.2 gallons (10 litres) of gin per person per year. The Sale of Spirits Act 1750 (commonly known as the Gin Act 1751) was an Act of the Parliament of Great Britain (24 Geo. 2. c. 40) which was enacted to reduce the consumption of gin and other distilled spirits, a popular pastime that was regarded as one of the primary causes of crime in London.

Modern period


The Andrew Johnson alcoholism debate is the dispute, originally conducted among the general public, and now typically a question for historians, about whether or not Andrew Johnson, the 17th president of the United States (1865–1869), drank to excess.

The Bratt System was a system that was used in Sweden (1919–1955) and similarly in Finland (1944–1970) to control alcohol consumption, by rationing of liquor. Every citizen allowed to consume alcohol was given a booklet called a motbok (viinakortti in Finland), in which a stamp was added each time a purchase was made at Systembolaget (in Sweden) and Alko (in Finland). A similar system also existed in Estonia between July 1, 1920 to December 31, 1925. The stamps were based on the amount of alcohol bought. When a certain amount of alcohol had been bought, the owner of the booklet had to wait until next month to buy more.

The Medicinal Liquor Prescriptions Act of 1933 was a law passed by Congress in response to the abuse of medicinal liquor prescriptions during Prohibition.

The rum ration (also called the tot) was a daily amount of rum given to sailors on Royal Navy ships. It started 1866 and was abolished in 1970 after concerns that the intake of strong alcohol would lead to unsteady hands when working machinery.

Gilbert Paul Jordan (aka The Boozing Barber) was a Canadian serial killer who is believed to have committed the so-called "alcohol murders" between 1965–c. 2004 in Vancouver, British Columbia.

Alcohol as a gateway drug
Alcohol and nicotine prime the brain for a heightened response to other drugs and are, like marijuana, also typically used before a person progresses to other, more harmful substances."

A study of drug use of 14,577 U.S. 12th graders showed that alcohol consumption was associated with an increased probability of later use of tobacco, cannabis, and other illegal drugs.