Warfarin is medication used to prevent blood clots from forming or growing larger in blood and blood vessels. Warfarin is in a class of medications called anticoagulants (*blood thinners) that works by decreasing the clotting ability of the blood. It is prescribed for people with certain types of irregular heartbeat, prosthetic heart valves, and for those who have had a heart attack. Warfarin is also used to treat or prevent venous thrombosis ( blood clot in a vein) and pulmonary embolism (a blood clot in the lung).

(* Some medications are commonly called blood thinners because they can help reduce a blood clot from forming. There are three main types of blood thinners that patients commonly take: anticoagulants like warfarin or heparin, antiplatelet drugs like aspirin, and fibrinolytics like tPA (tissue plasminogen activator). Each type of medication has a specific function to prevent a blood clot from forming or causing a blocked blood vessel, heart attack, or stroke.)

Return to Encyclopedia Home Image