Warfarin interactions with complementary medicines, herbs and dietary supplements

Sanjai Krishna S.and AiswaryaP

Abstract

Warfarin is a highly efficacious oral anticoagulant agent, whose use is limited by the well founded fear of bleeding. Many complementary medicines found to have potential interaction with warfarin and these interactions are marked as a cause of adverse events. The concomitant use of warfarin with drugs and herbal products leads to major safety concerns due to its narrow therapeutic window. Warfarin therapy is thought to interact with 250 different drugs. Various herbal products like cinchona , danshen, devil’s claw, dong quai, garlic, ginkgo, ginseng, Coenzyme Q10, ginseng, green tea, St John’s wort , vitamin K etc are thought to either increase or decrease the international normalized ratio. The purpose of this article is to serve a reference for pharmacists regarding the potential and documented interactions of warfarin with herbal products and dietary supplements associated with warfarin. In this review provide update information regarding the reported and documented interactions of warfarin.