Brand name: Coumadin
Warfarin is a medicine to treat/prevent harmful clots in the lungs (pulmonary embolism), veins (venous thrombosis), with abnormal heartbeat (atrial fibrillation), or after a heart valve replacement. The medicine also lowers the risk of stroke and other problems after the heart attack. It may also be used by your physician to treat certain other conditions.
It refers to anticoagulants. The medicine blocks the clotting factor synthesis. Blood clots are unable to form without these factors.