Disulfiram
Disulfiram is an aldehyde dehydrogenase inhibitor indicated as an aid in the management of chronic alcoholism. It produces an acute sensitivity to ethanol, resulting in a highly unpleasant reaction when alcohol is consumed, thereby providing a strong deterrent to drinking. This medication is most effective when used as part of a comprehensive treatment program.
Clinical Overview
Primary Clinical Applications
Disulfiram is indicated for chronic alcoholism as a deterrent to alcohol consumption. It is used in motivated patients who want to remain sober and is most effective when combined with counseling and psychosocial support. The medication helps maintain abstinence by creating negative consequences for alcohol use.
Mechanism and Clinical Benefits
Disulfiram irreversibly inhibits aldehyde dehydrogenase, causing accumulation of acetaldehyde when alcohol is consumed. This leads to the disulfiram-alcohol reaction characterized by flushing, nausea, vomiting, and other unpleasant symptoms, creating a powerful aversion to alcohol consumption.
Treatment Considerations
Patients must be alcohol-free for at least 12 hours before starting disulfiram. The reaction can occur with even small amounts of alcohol and may persist for up to 14 days after discontinuation. Careful patient selection and education are essential for safe and effective use.
Key Clinical Points
Twelve hours alcohol-free before the first dose
Starting disulfiram in a patient who has drunk within twelve hours precipitates the reaction it is meant to deter. Confirming abstinence is a prerequisite, not a formality.
The reaction can be fatal
Beyond flushing, headache, nausea and vomiting, the disulfiram-alcohol reaction can progress to respiratory depression, cardiovascular collapse, seizures, and death. Severity is not proportionate to the amount consumed.
Hidden alcohol sources need explicit counselling
Mouthwash, cough syrups, sauces, vinegars, and topical preparations can all trigger a reaction. Patients should carry identification indicating they are taking disulfiram.
Effect persists up to fourteen days after stopping
Irreversible enzyme inhibition means sensitivity outlasts the last dose by up to two weeks. Patients who stop in order to drink are still at risk during that window.
Contraindicated in psychosis and with metronidazole
Also contraindicated in severe myocardial disease and coronary occlusion. Regular liver function monitoring is required, and peripheral neuropathy can develop with prolonged use.
Prescribing Information
Dosing & Administration
Chronic Alcoholism:
- Initial: 500 mg daily for 1-2 weeks
- Maintenance: 250 mg daily (range 125-500 mg)
- Maximum: 500 mg daily
- Administration: Single dose in morning, with or without food
Pre-treatment Requirements:
- Patient must be alcohol-free for at least 12 hours
- Patient must be fully informed of risks
- Baseline liver function tests recommended
Indications
- Aid in management of chronic alcoholism
- Used as part of comprehensive treatment program
Contraindications
- Severe myocardial disease or coronary occlusion
- Psychoses
- Hypersensitivity to disulfiram or thiuram derivatives
- Recent alcohol consumption (within 12 hours)
- Metronidazole use
Warnings & Precautions
- Disulfiram-alcohol reaction: Can be severe or fatal
- Hepatotoxicity: Monitor liver function regularly
- Psychotic episodes: Risk in susceptible patients
- Peripheral neuropathy: With prolonged use
- Hidden alcohol sources: Warn about medications, foods, cosmetics
- Emergency treatment: Patients should carry identification card
Drug Interactions
- Alcohol: Severe disulfiram-alcohol reaction
- Metronidazole: Psychotic episodes reported
- Warfarin: Increased anticoagulant effect
- Phenytoin: Increased phenytoin levels
- Isoniazid: Coordination difficulties, psychotic episodes
Adverse Reactions
Without Alcohol:
- Drowsiness, fatigue, headache, metallic taste
Disulfiram-Alcohol Reaction:
- Flushing, throbbing headache, nausea, vomiting, chest pain
Serious:
- Respiratory depression, cardiovascular collapse, seizures, death
Special Populations
- Hepatic impairment: Monitor liver function closely
- Pregnancy: Category C – use only if clearly needed
- Elderly: Increased sensitivity to adverse effects
- Diabetes: Monitor for hypoglycemia
Frequently Asked Questions
What is Disulfiram used for?
Disulfiram is an aldehyde dehydrogenase inhibitor indicated as an aid in the management of chronic alcoholism. It produces an acute sensitivity to ethanol, resulting in a highly unpleasant reaction when alcohol is consumed, thereby providing a strong deterrent to drinking. This medication is most effective when used as part of a comprehensive treatment program.
What class of drug is Disulfiram?
Disulfiram is classified as: Aldehyde Dehydrogenase Inhibitor.
Twelve hours alcohol-free before the first dose?
Starting disulfiram in a patient who has drunk within twelve hours precipitates the reaction it is meant to deter. Confirming abstinence is a prerequisite, not a formality.
The reaction can be fatal?
Beyond flushing, headache, nausea and vomiting, the disulfiram-alcohol reaction can progress to respiratory depression, cardiovascular collapse, seizures, and death. Severity is not proportionate to the amount consumed.
Hidden alcohol sources need explicit counselling?
Mouthwash, cough syrups, sauces, vinegars, and topical preparations can all trigger a reaction. Patients should carry identification indicating they are taking disulfiram.
Effect persists up to fourteen days after stopping?
Irreversible enzyme inhibition means sensitivity outlasts the last dose by up to two weeks. Patients who stop in order to drink are still at risk during that window.
Source: FDA prescribing information (DailyMed)