[Alcohol and drug interactions].
Alcohol metabolism occurs mainly in the liver, where in abstainers the alcoholdehydrogenase (ADH) pathway plays the major role. After chronic alcohol consumption, the microsomal ethanol-oxidizing system (MEOS), involving the ethanol-inducible cytochrome P450 2E1, increases in importance with a four- to ten-fold increase in the contribution to alcohol metabolism. Because of the fact that this enzyme system catalyses not only the metabolism of ethanol but also activates a great number of drugs, it is a very common site of alcohol-drug interactions. Clinically relevant interactions will be discussed. Only a small amount of alcohol is metabolized outside the liver, mainly in the stomach by gastric ADH, which leads to the so-called first-pass metabolism of ethanol. Its significance in alcohol metabolism is reviewed. The only way to prevent severe alcohol-drug interactions is to make medical doctors as well as their patients more aware of these possible secondary effects.
Oneta
C M
CM
Département de Médecine interne, CHUV/PMU, Lausanne. Carl.Oneta@chuv.hospvd.ch
D000429:Alcohol Oxidoreductases / Q000502:physiology; D019973:Alcohol-Related Disorders / Q000201:enzymology*; D019392:Cytochrome P-450 CYP2E1 / Q000502:physiology; D003577:Cytochrome P-450 Enzyme System / Q000502:physiology; D004347:Drug Interactions / Q000502:physiology; D000431:Ethanol / Q000493:pharmacokinetics; D006801:Humans; D008111:Liver Function Tests
D000431:Ethanol; D003577:Cytochrome P-450 Enzyme System; D000429:Alcohol Oxidoreductases; C092153:microsomal ethanol-oxidizing system; D019392:Cytochrome P-450 CYP2E1