High-dose omega-3 fatty acids (>3g/day EPA+DHA) have antiplatelet effects and may potentiate warfarin's anticoagulation, increasing bleeding risk. Mechanism involves reduced thromboxane A2 synthesis and altered platelet membrane fluidity.
Recommendation
Inform doctor if taking fish oil with warfarin. May need INR monitoring. Doses under 1g/day generally safe.
Timing
Monitor for bleeding signs; bruising, bloody nose, dark stools
Sources
— American Journal of Cardiology
— PMID: 15072218
— PMID: 17056120
Frequently Asked Questions
Can I take omega-3 and warfarin together?
Fish oil may increase bleeding risk with warfarin. Inform doctor if taking fish oil with warfarin. May need INR monitoring. Doses under 1g/day generally safe.
How should I time omega-3 and warfarin?
Monitor for bleeding signs; bruising, bloody nose, dark stools
Is this interaction dangerous?
This interaction is rated “Warning” by Formulate. High-dose omega-3 fatty acids (>3g/day EPA+DHA) have antiplatelet effects and may potentiate warfarin's anticoagulation, increasing bleeding risk. Mechanism involves reduced thromboxane A2 synthesis and altered platelet membrane fluidity.
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