User talk:Ranaran35/sandbox

A number of opioids undergo metabolism by cytochrome P450 enzymes in order to generate active metabolites. Only by generating these active metabolites can analgesic effects occur. The enzyme CYP2D6 is used to metabolize several opioids including codeine, methadone, hydrocodone, and tramadol. The level of expression of CYP2D6 can vary dramatically between different individuals. Individuals with low expression of CYP2D6 are designated as poor metabolizers while individuals with high expression of CYP2D6 are designated as ultra-rapid metabolizers. This information is important for healthcare professionals to know as it determines the dose of opioids a patient will need in order to achieve the desired analgesic effect. If given the same starting dose of codeine, a poor metabolizer will feel very little pain relief while an ultra-rapid metabolizer may feel a large reduction in pain. Conversely patients who are ultra-rapid metabolizers should be given minimal amounts of opioids such as tramadol in order to avoid respiratory depression. Information regarding a patient's CYP2D6 expression can be found by running a genomic test such as 23andMe. This information is also helpful to healthcare professionals so they may modify the dosing of other drugs that may have drug-drug interactions with opioids such as rifampin.[20]

Gong, Li, et al. “PharmGKB Summary.” Pharmacogenetics and Genomics, vol. 24, no. 7, July 2014, pp. 374–380., doi:10.1097/fpc.0000000000000057.