Disulfiram Side Effects: What to Expect and When to Call Your Doctor

Disulfiram has two distinct categories of side effects that are important to understand: those that occur even without drinking alcohol, and the potentially severe disulfiram-alcohol reaction (DAR) that occurs when alcohol is consumed. Understanding both will help you know what to watch for, when to contact your doctor, and when to seek emergency care.

Side Effects When You Don't Drink Alcohol (Baseline Side Effects)

When taken as prescribed without any alcohol exposure, most people tolerate disulfiram reasonably well. Common baseline side effects typically appear during the first one to two weeks of therapy and often resolve on their own:

• Metallic or garlic-like taste: One of the most commonly reported side effects. Usually mild and improves over time.
• Drowsiness and fatigue: Some patients feel sedated, especially in the first few weeks. Taking disulfiram at bedtime instead of morning can help minimize daytime drowsiness.
• Headache: Mild headaches are common early in treatment.
• Acneform eruptions: Some patients develop acne-like skin changes. These are usually manageable with standard skin care or antihistamines.
• Impotence: Reported in some male patients, particularly at higher doses.
• Allergic dermatitis: Skin rashes can occur. Often manageable; notify your doctor if severe.

The Disulfiram-Alcohol Reaction: What Happens If You Drink

This is the intended mechanism of disulfiram, but it can become a medical emergency. The reaction begins within 10-30 minutes of consuming even a small amount of alcohol and typically lasts 30-60 minutes (though it can persist for several hours if large amounts were consumed).

Mild to moderate symptoms include:

• Flushing and throbbing headache
• Nausea and vomiting
• Sweating, dizziness, and weakness
• Rapid heart rate (tachycardia) and low blood pressure
• Shortness of breath and chest discomfort
• Blurred vision and confusion

Severe reactions (especially with large amounts of alcohol) may include:

• Respiratory depression — breathing becomes dangerously slow
• Cardiac arrhythmias or heart attack
• Cardiovascular collapse and unconsciousness
• Death (rare, but documented, especially in patients with pre-existing heart disease)

Call 911 immediately if you or someone on disulfiram has a severe reaction after drinking. This is a medical emergency.

Serious Side Effects That Require Calling Your Doctor

Even without alcohol exposure, these side effects require prompt medical attention:

• Signs of liver problems: Upper right abdominal pain, nausea/loss of appetite, dark urine, yellowing of skin or eyes (jaundice), pale stools. Disulfiram has caused hepatitis and liver failure — some fatal.
• Mental/mood changes: Confusion, paranoia, hallucinations, or severe depression. Psychosis has been reported, especially at higher doses.
• Numbness or tingling in extremities: May indicate peripheral neuropathy, a rare but documented adverse effect. Occurs in approximately 1 per 1,000 patients per year.

Hidden Alcohol Sources to Avoid

Even small amounts of alcohol can trigger the disulfiram-alcohol reaction. Be cautious of:

• Mouthwash and toothpaste (some contain alcohol)
• Cough syrups, liquid medications (check labels)
• Vinegar-based foods, fermented products (kombucha, sauerkraut)
• After-shave, colognes, and alcohol-containing skin products (may absorb transdermally)
• Certain injectable or oral medications (e.g., ritonavir oral solution contains 42% alcohol)

For a complete list of medications that interact with disulfiram, see our guide on disulfiram drug interactions.

Having trouble finding disulfiram at your pharmacy? medfinder can contact pharmacies near you to find which ones have it in stock.