Fish Oil Interactions

Apixaban is a direct factor Xa inhibitor that raises bleeding risk on its own. Omega-3 fatty acids in fish oil have a mild antiplatelet effect that can theoretically add to that risk. A large 2024 systematic review and meta-analysis found that typical supplement-level omega-3 intake did not significantly raise bleeding risk, with only a small absolute increase seen at very high, prescription-strength doses. Standard fish oil is generally compatible with apixaban when the prescriber is aware, while high-dose omega-3 should be cleared with a clinician.

Fish oil may modestly add to bleeding risk when combined with warfarin, though most people on stable doses show little change in INR.

Omega-3 fatty acids in fish oil have a mild antiplatelet effect, slightly shifting platelet thromboxane production and modestly lengthening bleeding time. Rivaroxaban blocks Factor Xa to reduce clotting. The two act through different pathways, so the combination is additive in theory, but clinical evidence suggests the real-world bleeding effect is small. A large randomized trial found no increase in bleeding even with high-dose fish oil.

Omega-3 fatty acids in fish oil mildly reduce platelet aggregation, which in theory adds to aspirin's antiplatelet effect. In practice, clinical studies have not found a clinically significant increase in major bleeding when standard fish oil is combined with aspirin.

Naproxen and fish oil both mildly reduce platelet aggregation through separate pathways, so their effects are additive in theory. Pooled clinical-trial data show no meaningful increase in major bleeding at typical doses.