Theophylline and Albendazole: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Jul 10, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Albendazole
Theophylline
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
An increased risk of theophylline toxicity (nausea, vomiting, palpitations, seizures)
Interaction Deep Dive
The pharmacokinetics of theophylline were unaltered by albendazole in a single dose study1. However, albendazole is known to inhibit hepatic cytochrome P450 1A, an isoenzyme involved in theophylline metabolism. Until more data are available, the manufacturer of albendazole recommends that theophylline serum concentrations should be monitored during and after concurrent therapy 2.
Why it happens (mechanism)
Inhibition by albendazole of theophylline metabolism
Literature reports
1 report — tap to read
a) In one study, six healthy volunteers received a single dose of albendazole 400 mg followed by aminophylline 5.8 mg/kg infused over 20 minutes two hours later in an open, randomized, cross-over design. Each phase was separated by one week. Theophylline half-life, volume of distribution, and total body clearance were not altered by the administration of albendazole 1.
Common questions
Can I take Theophylline and Albendazole together?
An increased risk of theophylline toxicity (nausea, vomiting, palpitations, seizures) Always confirm with your pharmacist or prescriber before making any change.
How serious is the Theophylline and Albendazole interaction?
It is rated minor. Usually limited clinical impact.
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 "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Theophylline or Albendazole 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)
Keep reading about Albendazole
Keep reading about Theophylline
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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