Atomoxetine and Warfarin Interaction
Drug interaction information between Atomoxetine and Warfarin.
Atomoxetine and Warfarin have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Atomoxetine 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.
How They Interact
Atomoxetine does not interfere with how warfarin attaches to proteins in the blood, so it should not change how well the blood thinner works.
What To Do
No dosage adjustments are typically required for this combination.
FDA Label Information
Atomoxetine did not affect the binding of warfarin, acetylsalicylic acid, phenytoin, or diazepam to human albumin.
Atomoxetine Also Interacts With
- Albuterol moderate
- Omeprazole minor
- Fluoxetine minor
- Methylphenidate minor
- Diazepam minor
Warfarin Also Interacts With
- Fluoxetine major
- Tamoxifen major
- Ibuprofen moderate
- Aspirin moderate
- Diclofenac moderate
Frequently Asked Questions
Can I take Atomoxetine and Warfarin together?
This is a minor interaction. No dosage adjustments are typically required for this combination.
How serious is the interaction between Atomoxetine 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 Atomoxetine and Warfarin interact?
Atomoxetine does not interfere with how warfarin attaches to proteins in the blood, so it should not change how well the blood thinner works.
Understanding the Atomoxetine and Warfarin Interaction
FDA-approved prescribing information for these two drugs flags their combination as a minor-severity interaction. Atomoxetine belongs to the Selective Norepinephrine Reuptake Inhibitor 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: Atomoxetine does not interfere with how warfarin attaches to proteins in the blood, so it should not change how well the blood thinner works. 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. Atomoxetine has 15 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 dosage adjustments are typically required for this combination. 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 Atomoxetine 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.
Read our methodology - how this data is sourced, computed, and verified.