Title: Acute Warfarin Toxicity due to Interaction between Warfarin and Amiodarone
Authors: Dr M. Ajeeth Fera, Dr S. Balasubramaniyan, Dr N. Paari, Dr P.Sankara Thiagarajan, Dr B.Nandini Priyanka
DOI: https://dx.doi.org/10.18535/jmscr/v5i10.128
Abstract
Warfarin is an anticoagulant that's broadly used in the treatment and prevention of thrombosis, in the treatment of dilated cardiomyopathy, mechanical valves, pulmonary embolism and atrial fibrillation. Amiodarone was initially introduced as an anti-anginal drug over 40 years ago but is now used therapeutically as a Class III antiarrhythmic agent. Amiodarone is associated with adverse effects like pulmonary toxicity, hepatotoxicity and thyroid disorder. There have been reviews of unfavorable drug interactions when amiodarone is administered together with a wide range of different therapeutic agents like theophylline and flecainide . However, the most common, probably the maximum risky drug interaction that amiodarone exhibits is its potentiation of the anticoagulant effect of warfarin, which substantially increases the patient’s risk of hemorrhage. Polymorphisms in cytochrome P450 genes and drug interactions are accountable for most of the warfarin toxicity. Each person is different in their susceptibity to drugs. Here we report a case in our article, which is an example of one such interaction of warfarin with amiodarone.
Keywords: Warfarin, Amiodarone.
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