We have already discussed some important factors that affect drug metabolism, including genetic polymorphisms, enzyme inhibition, enzyme induction, and first-pass metabolism. You should be aware by now that there is a great deal of variation in the metabolic reactions that produce drug metabolites. The extent to which a drug is metabolized by one individual can be dramatically different than that of another. Thus, the effect a drug will have on one individual can be dramatically different than the effect it has on another.
