ABSTRACT
The majority of western populations drink alcohol some occasionally, some regularly and moderately, and some excessively. The truism is important for the prescriber, because alcohol has paradoxical effects on P450 liver enzymes which metabolise other drugs (see ), dependent on the person's drinking habits. Alcohol itself is metabolised stepwise by two enzymes, alcohol dehydrogenase and aldehyde dehydrogenase, and to a lesser extent by a P450 enzyme. Unfortunately, the availability of these enzymes for alcohol is limited, and the metabolic capacity is saturated after only a few drinks. The remaining alcohol after a 'night out' is slowly metabolised over the next 12 hours or more hence the drink-driving convictions the 'morning after.' Most prescribers know that the alcohol aversion drug, disulfiram (Antabuse), causes a progressive series of very unpleasant symptoms, depending on the dose of alcohol consumed.
