US Pharm. 2010;35(12):8. 

Salt Lake City, UT-- Researchers from the Intermountain Medical Center Heart Institute in Salt Lake City, Utah, interviewed 100 patients with atrial fibrillation to assess their understanding of potential interactions between herbal and dietary supplements and the widely prescribed blood thinner warfarin. They found that of 35 patients combining warfarin with supplements, 54% were unaware of potential interactions. These results are alarming, as 69 of the 100 most commonly used supplements, including fish oil, coenzyme Q10, and many vitamins, interfere with the effectiveness of warfarin. These interactions can either intensify or reduce the drug's effectiveness, increasing the risk of bleeding or stroke. “Physicians must be active in asking about supplement use and not place responsibility on patients,” said T. Jared Bunch, MD, a study author and heart rhythm specialist. 

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