Fish Oil and Coumadin: Understanding Interactions and Benefits

Coumadin is the proprietary name for a prescription anticoagulant (blood-thinner) known as sodium warfarin. Fish oil capsules contain concentrated amounts of alpha tocopheryl, docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA).

Indications

• If you're at high risk for strokes, heart attacks, and/or deep venous thromboses (DVTs), your doctor may prescribe Coumadin to thin your blood and prevent clot formation. According to the Mayo Clinic, there is solid evidence that fish oil also reduces your risk of clots.

Sources

• Coumadin is a prescription drug approved by the FDA and manufactured under controlled circumstances. Fish oil capsules are over-the-counter natural products that derive their contents from a variety of fish.

Interactions

• According to Medscape's Drug Interaction Checker, fish oil can interact with Coumadin in a way that increases the blood-thinning properties of both drugs. The risk of interaction is highest when you are on one of the drugs and then either start or stop taking the second drug.

Significance

• The interaction between alpha tocopheryl and Coumadin can be severe, which means you should take action to lower your risk for bleeding. It's not a good idea to take these two drugs together.

Warning

• According to Dr. Andrew Weil, fish oil supplements may include various amounts of toxins found in fish, including PCBs. You can limit your exposure by picking a brand that's been distilled to remove toxins.