[Effects of hepato-biliary diseases on drug metabolism (author's transl)].

Drug metabolism may be impaired in patients with hepato-biliary diseases. Hepatocellular failure may decrease the rate of drug biotransformation; cholestasis may decrease 1) the absorption of lipid soluble drugs, 2) the rate of drug biotransformation, and 3) the biliary excretion of drugs. Activity and/or toxicity are modified variously as either the drug or a metabolite of it is the active and/or toxic compound. Although there is an obvious need for an adapted posology in patients with liver diseases, only suggestions can be drawn from presently limited data.