warfarin, Coumadin, Jantoven

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GENERIC NAME: warfarin

BRAND NAME: Coumadin, Jantoven

DRUG CLASS AND MECHANISM: Warfarin is an oral anticoagulant, a drug that inhibits the clotting of blood. It prevents the formation of blood clots by reducing the production of factors by the liver that promote clotting, factors II, VII, IX, and X, and the anticoagulant proteins C and S. The production of these factors by the liver are dependent on adequate amounts of vitamin K. Warfarin reduces the production of the factors because it antagonizes vitamin K. Blood clots can occur in the veins of the lower extremities (deep venous thrombosis [DVT]), often after periods of immobility. These clots can break off and become lodged in the blood vessels of the lung (pulmonary embolism), causing shortness of breath, chest pain, and even life-threatening shock. Blood clots can also occur in the atria of the heart during atrial fibrillation and around artificial heart valves. These clots also can break off and obstruct blood vessels in the brain, causing an embolic stroke with paralysis. Warfarin is important in preventing the formation of blood clots, preventing extension of clots already formed, and minimizing the risk of embolization of blood clots to other vital organs such as the lungs and brain. The FDA approved warfarin in June 1954.

Medically Reviewed by a Doctor on 1/4/2013



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