Theophylline and Disulfiram: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Theophylline
Disulfiram
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Theophylline toxicity (nausea, vomiting, palpitations, seizures)
Interaction Deep Dive
Disulfiram inhibits the metabolism of theophylline in a dose-dependent relationship12.
Why it happens (mechanism)
Decreased theophylline metabolism
Literature reports
1 report — tap to read
a) Twenty alcoholics were given theophylline 5 mg/kg plus either disulfiram 250 mg (n=10) or disulfiram 500 mg (n=10). The theophylline plasma clearance was decreased (15% to 30% and 20% to 49%, respectively) and the elimination half-life was increased (20% and 30%, respectively), with the magnitude dependent upon the disulfiram dose. A theophylline dose reduction as high as 50% may be necessary in patients concomitantly receiving disulfiram 1.
Common questions
Can I take Theophylline and Disulfiram together?
Theophylline toxicity (nausea, vomiting, palpitations, seizures) Always confirm with your pharmacist or prescriber before making any change.
How serious is the Theophylline and Disulfiram interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "delayed". Effects tend to build up gradually over days to weeks.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Theophylline or Disulfiram need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there anything you'd monitor while I'm on both?
References (2)
- Loi CM, Day JD, Jue SG, et al: Dose-dependent inhibition of theophylline metabolism by disulfiram in recovering alcoholics. Clin Pharmacol Ther 1989; 45:476-486. PubMed
- Upton RA: Pharmacokinetic interactions between theophylline and other medication (part 1). Clin Pharmacokinet 1991; 20:66-80.
Keep reading about Theophylline
Keep reading about Disulfiram
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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