Montelukast and Theophylline Interaction
Drug interaction information between Montelukast and Theophylline.
Montelukast and Theophylline have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Montelukast and Theophylline. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.
How They Interact
Taking these two drugs together does not affect how much of either medicine stays in your body.
What To Do
You can continue taking your usual doses of both medications.
FDA Label Information
DRUG INTERACTIONS No dose adjustment is needed when montelukast sodium is co-administered with theophylline, prednisone, prednisolone, oral contraceptives, terfenadine, digoxin, warfarin, gemfibrozil, itraconazole, thyroid hormones, sedative hypnotics, non-steroidal anti-inflammatory agents, benzodiazepines, decongestants, and Cytochrome P450 (CYP) enzyme inducers [see Clinical Pharmacology (12.3)] .
Montelukast Also Interacts With
- Prednisone minor
- Warfarin minor
- Prednisolone minor
- Itraconazole minor
- Digoxin minor
Theophylline Also Interacts With
- Metoprolol major
- Albuterol major
- Omeprazole major
- Amoxicillin major
- Famotidine major
Frequently Asked Questions
Can I take Montelukast and Theophylline together?
This is a minor interaction. You can continue taking your usual doses of both medications.
How serious is the interaction between Montelukast and Theophylline?
This interaction is classified as "minor" severity by the FDA. Minor interactions are unlikely to cause significant problems but should still be mentioned to your healthcare provider.
Why do Montelukast and Theophylline interact?
Taking these two drugs together does not affect how much of either medicine stays in your body.
Understanding the Montelukast and Theophylline Interaction
FDA-approved prescribing information for these two drugs flags their combination as a minor-severity interaction. Montelukast belongs to the Leukotriene Receptor Antagonist class and Theophylline belongs to the Methylxanthine Bronchodilator class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Taking these two drugs together does not affect how much of either medicine stays in your body. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.
Context around a specific patient determines real-world impact. Montelukast has 8 total documented interactions on file in this dataset, and Theophylline has 86. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: You can continue taking your usual doses of both medications. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.
An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Montelukast or Theophylline based on a web page, speak with your prescriber or pharmacist before making any change.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.
Read our methodology - how this data is sourced, computed, and verified.