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omega-3 and warfarin

Fish oil may increase bleeding risk with warfarin

What's happening

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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Cited research

Studies from our registry that mention omega-3 or warfarin. Each links to the primary source and the other Formulate pages citing it.

Related reading

Other interactions to know

More interactions involving omega-3 or warfarin

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Medical disclaimer. This page is for educational purposes only and does not replace advice from a qualified healthcare provider.

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