Fosinopril and Warfarin Interaction
Drug interaction information between Fosinopril and Warfarin.
Fosinopril and Warfarin have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Fosinopril 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
These drugs do not change how the body absorbs each other, and fosinopril does not affect how well the blood thinner works to prevent clots.
What To Do
You can safely take these together, though your doctor will continue to monitor your routine blood clotting tests as usual.
FDA Label Information
In separate single or multiple dose pharmacokinetic interaction studies with chlorthalidone, nifedipine, propranolol, hydrochlorothiazide, cimetidine, metoclopramide, propantheline, digoxin, and warfarin, the bioavailability of fosinoprilat was not altered by coadministration of fosinopril with any one of these drugs. In a pharmacokinetic interaction study with warfarin, bioavailability parameters, the degree of protein binding, and the anticoagulant effect (measured by prothrombin time) of warfarin were not significantly changed.
Fosinopril Also Interacts With
- Aliskiren major
- Lithium moderate
- Hydrochlorothiazide minor
- Aspirin minor
- Propranolol minor
Warfarin Also Interacts With
- Fluoxetine major
- Tamoxifen major
- Ibuprofen moderate
- Aspirin moderate
- Diclofenac moderate
Frequently Asked Questions
Can I take Fosinopril and Warfarin together?
This is a minor interaction. You can safely take these together, though your doctor will continue to monitor your routine blood clotting tests as usual.
How serious is the interaction between Fosinopril 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 Fosinopril and Warfarin interact?
These drugs do not change how the body absorbs each other, and fosinopril does not affect how well the blood thinner works to prevent clots.
Understanding the Fosinopril and Warfarin Interaction
FDA-approved prescribing information for these two drugs flags their combination as a minor-severity interaction. Fosinopril belongs to the ACE 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: These drugs do not change how the body absorbs each other, and fosinopril does not affect how well the blood thinner works to prevent clots. 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. Fosinopril has 12 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: You can safely take these together, though your doctor will continue to monitor your routine blood clotting tests as usual. 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 Fosinopril 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.