Warfarin

An anticoagulant drug used to treat and prevent abnormal blood clotting. Warfarin is used to treat deep vein thrombosis, pulmonary embolism, and people with atrial fibrillation who are at risk of an embolism. It is also prescribed to prevent emboli from developing on replacement valves (see heart-valve surgery). A faster-acting anticoagulant, such as heparin, may also be prescribed for the first few days following a deep-vein thrombosis or pulmonary embolism. Warfarin may cause abnormal bleeding in different parts of the body, so regular tests are carried out to allow careful regulation of dosage. Warfarin may also cause nausea, diarrhoea and a rash.