The properties that promote drug interactions:
Chronic alcoholism results in enzyme induction. Acute alcoholic intoxication tends to inhibit drug metabolism (whether the person is an alcoholic or not). Severe alcohol-induced hepatic dysfunction may inhibit ability to metabolize drugs. Disulfiram (Antabuse) like reactions in the presence of certain drugs may occur. Additive CNS (central nervous system) depression with other central nervous depressants may occur.
Clinically documented alcohol-drug interactions:
Acetaminophen:
Increased formation of hepatotoxic acetaminophen metabolites (in chronic alcoholics)
Anticoagulants, oral:
Increased hypoprothrombinaemic effect with acute alcohol intoxication.
Central Nervous System depressants:
Additive or synergistic CNS depression.
Insulin:
Acute alcohol intake may increase hypoglycaemic effect of insulin (especially in fasting patients).
Drugs that produce a disulfiram-like reaction:
- Cephalosporins: Disulfiram-like reactions noted with cefamandole, cefaperazone, cefotetan and moxalactam.
- Chloral hydrate: Mechanism not established.
- Disulfiram: Inhibits aldehyde dehydrogenase.
- Metronidazole: Mechanism not established.
- Sulfonylureas: Chlorpropamide is most likely to cause a disulfiram-like reaction; acute alcohol intake may increase hypoglycemic effect (especially in fasting patients)