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Montelukast and Warfarin Interaction

Drug interaction information between Montelukast and Warfarin.

Montelukast and Warfarin have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Montelukast and Warfarin. 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.

Drug A

Montelukast

Leukotriene Receptor Antagonist

Drug B

Warfarin

Vitamin K Antagonist (Anticoagulant)

How They Interact

These two medicines do not interfere with each other, so they do not change how the other drug is processed.

What To Do

No dose changes are needed when you take these two medicines at the same time.

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)] .

Warfarin Also Interacts With

View all Warfarin interactions →

Frequently Asked Questions

Can I take Montelukast and Warfarin together?

This is a minor interaction. No dose changes are needed when you take these two medicines at the same time.

How serious is the interaction between Montelukast and Warfarin?

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 Warfarin interact?

These two medicines do not interfere with each other, so they do not change how the other drug is processed.

Understanding the Montelukast and Warfarin 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 Warfarin belongs to the Vitamin K Antagonist (Anticoagulant) class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: These two medicines do not interfere with each other, so they do not change how the other drug is processed. 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 Warfarin has 163. 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: No dose changes are needed when you take these two medicines at the same time. 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 Warfarin 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.