Does Disulfiram Cause Eosinophilia?
Yes, disulfiram can cause eosinophilia as part of a hypersensitivity hepatitis reaction, though this is an uncommon adverse effect.
Evidence from Drug Labeling and Case Reports
The FDA drug label for disulfiram does not specifically list eosinophilia as a standalone adverse effect 1. However, published case reports clearly document disulfiram-induced hepatitis accompanied by eosinophilia as a manifestation of hypersensitivity reaction.
Two well-documented cases demonstrate this association:
A 1990 case report described a patient who developed headache, mild fever, nausea, vomiting, rash, and eosinophilia after 3 weeks of disulfiram therapy. Liver biopsy showed low-grade lobular hepatitis, and all symptoms including eosinophilia resolved after discontinuing disulfiram 2.
A 1989 case documented a 38-year-old woman taking disulfiram 500 mg daily who presented after approximately 2 weeks with anorexia, vomiting, fatigue, right upper-quadrant pain, pruritus, darkened urine, and jaundice. Laboratory findings showed significantly elevated eosinophils along with elevated hepatocellular enzymes and total bilirubin. After disulfiram discontinuation, both clinical and biochemical manifestations resolved 3.
Mechanism and Clinical Pattern
The mechanism appears to be an allergic or hypersensitivity reaction rather than direct drug toxicity 3. This is consistent with the clinical pattern observed:
- Timing: Eosinophilia typically develops within 2-3 weeks of starting disulfiram
- Associated features: Usually occurs alongside hepatitis symptoms (fatigue, weakness, malaise, anorexia, nausea, vomiting, jaundice, dark urine)
- Additional manifestations: May include fever, rash, and elevated liver enzymes
- Resolution: Eosinophilia resolves after drug discontinuation
Clinical Implications
If a patient on disulfiram develops eosinophilia, immediately:
- Check liver function tests (AST, ALT, bilirubin, alkaline phosphatase)
- Assess for hepatitis symptoms (fatigue, weakness, nausea, jaundice, dark urine)
- Discontinue disulfiram if hepatotoxicity is suspected
- Monitor complete blood count and liver function until normalization
The FDA label emphasizes that patients should be advised to immediately notify their physician of any early symptoms of hepatitis 1. Baseline and follow-up liver function tests at 10-14 days are suggested to detect hepatic dysfunction 1.
Important Caveats
- Eosinophilia from disulfiram is not a common adverse effect but occurs as part of a hypersensitivity syndrome
- The presence of eosinophilia should raise concern for hepatotoxicity, which can be severe and sometimes fatal 1
- Disulfiram should already be avoided in patients with severe alcoholic liver disease due to hepatotoxicity risk 4
- The drug is contraindicated in pregnancy due to fetal abnormalities 5
Bottom line: While not a frequent occurrence, disulfiram-associated eosinophilia is a recognized manifestation of hypersensitivity hepatitis and warrants immediate evaluation for liver injury and drug discontinuation.