WARFARIN

Originally developed to treat thromboembolism (see {{link=thrombosis">thrombosis ), it interferes with the liver's metabolism of vitamin K , leading to production of defective coagulation factors. Warfarin therapy risks uncontrollable hemorrhage , either spontaneously or from any cut or bruise; it requires frequent checks to maintain the proper level in the blood. In high concentrations, warfarin is used as a rodent poison, causing death by internal bleeding.