Can You Take Warfarin & Fish Oil Together?

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Fish oil supplements are a naturally blood thinner. The benefits of fish oil include slightly lower blood pressure, reduced triglycerides as well as decreased heart arrhythmias. Additional benefits include possible reduction of plaque and hardening of the arteries, also known as atherosclerosis. Warfarin, sold under the brand name Coumadin, is also a blood thinner. Taking fish oil and warfarin together can cause serious side effects.


Do not take a fish oil supplement and warfarin together because of the risk of bleeding complications. Both the supplement and the medication decrease blood clotting time and increase bleeding. Other blood thinning drugs have the same effect including aspirin, heparin, dipyridamole and ticlopidine. Don’t forget, besides warfarin, herbal supplements may also have the same effect. Some herbal supplements to avoid when taking fish oil include ginkgo, garlic, turmeric, willow and red clover.

Side Effects

Taking the medications together can cause nose bleeds, skin to bruise, internal gastric bleeding as well as a hemorrhagic stroke to occur. These symptoms may even occur when only taking fish oil or warfarin alone. Discuss with your medical professional the proper dose of the supplement or medication you should be taking.


Consider avoiding fish oil supplements and eating fresh seafood twice a week. The American Heart Association suggests Americans consume two 3.5-oz servings of fish a week for omega-3 fatty acid benefits. Remember to bake and not pan fry your fish. Eat fatty fish such as salmon, tuna and herring that contain the most amount of omega-3 fatty acids.

Additional Warnings

If you suffer from severe heart disease, regular severe angina and heart irregularities avoid taking fish oil. Even though fish oil supplements are considered heart-healthy, for some people the supplement can make conditions worse. According to Harvard Medical School, fish oil supplements may actually increase symptoms and lead to a heart attack, stroke or death. People with arterial defibrillators installed should also not consume fish oil supplements to avoid the risk of extreme heart arrhythmias.