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Alcohol Deterrent (Aldehyde Dehydrogenase Inhibitor) Pregnancy: Contraindicated — teratogenic in animals; disulfiram-alcohol reaction could be harmful to fetus. Do not use in pregnancy.

Disulfiram

Brand names: Antabuse

Adult dose

Dose: 400–500mg OD for 1–2 weeks initially; reduce to maintenance 200mg OD. Must be abstinent from alcohol for at least 24 hours before first dose.
Route: Oral
Frequency: Once daily (preferably supervised — morning dose given by carer or pharmacy)
Max: 500mg OD
Mechanism: irreversible inhibition of aldehyde dehydrogenase (ALDH) — alcohol ingestion causes acetaldehyde accumulation → flushing, palpitations, nausea, hypotension, dyspnoea. Reaction can occur up to 14 days after stopping disulfiram (enzyme regeneration takes 1–2 weeks). Patient must be fully counselled and consent obtained — not given covertly. Avoid all alcohol sources: mouthwash, vinegar, sauces, hand sanitisers applied near mouth, some medications.

Paediatric dose

Route: Oral
Frequency: Once daily
Max: Not applicable
Not licensed under 18 years. Alcohol dependence treatment in adolescents: seek specialist addiction psychiatry opinion.

Dose adjustments

Renal

Use with caution in renal impairment.

Hepatic

Contraindicated in severe hepatic impairment — hepatotoxicity risk; liver failure reported.

Clinical pearls

  • Disulfiram reaction antidote: if severe reaction occurs — IV fluids for hypotension, oxygen, antihistamines (chlorphenamine); in life-threatening reaction — 4-methylpyrazole (fomepizole) inhibits alcohol metabolism further upstream; manage in ICU
  • Supervised consumption improves efficacy significantly — pharmacy supervision or carer-administered dosing reduces covert alcohol use
  • Hepatotoxicity monitoring: LFTs at baseline, 2 weeks, 4 weeks, then every 6 months — stop if LFTs >3× ULN
  • Rubber allergy: disulfiram is a thiuram compound — patients with rubber/latex allergy may have cross-sensitivity; ask before prescribing

Contraindications

  • Cardiac failure or severe coronary artery disease
  • Psychosis (current or recent)
  • Severe hepatic impairment or cirrhosis
  • Pregnancy
  • Patient unable to give informed consent
  • Suicidal ideation (disulfiram reaction could be used as self-harm method)
  • Hypersensitivity to disulfiram or thiuram compounds (rubber allergy)

Side effects

  • Disulfiram-alcohol reaction: flushing, throbbing headache, nausea, vomiting, hypotension, tachycardia, dyspnoea — severity proportional to alcohol dose (can be fatal in severe cases)
  • Drowsiness and fatigue (early)
  • Peripheral neuropathy (prolonged use)
  • Hepatotoxicity (idiosyncratic — rare but serious; LFT monitoring required)
  • Metallic or garlic taste
  • Psychosis (rare — dopamine beta-hydroxylase inhibition increases dopamine)

Interactions

  • Alcohol — disulfiram reaction (therapeutic mechanism — see notes)
  • Metronidazole, tinidazole — disulfiram-like reaction WITHOUT alcohol; avoid combination
  • Warfarin — disulfiram inhibits warfarin metabolism; INR rises significantly; reduce warfarin dose and monitor INR closely
  • Phenytoin — disulfiram inhibits phenytoin metabolism; toxicity risk; monitor levels
  • Isoniazid — CNS toxicity (ataxia, psychosis) when combined; avoid

Monitoring

  • LFTs (baseline, 2 weeks, 4 weeks, then 6 monthly)
  • Alcohol abstinence (urine ethyl glucuronide or breathalyser)
  • Neurological symptoms (peripheral neuropathy — long-term)
  • Mood and psychosis screening

Reference: BNFc; BNF 90; NICE CG115 (Alcohol Dependence); NICE NG115. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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