Used as an anticoagulant to prevent blood clot formation, particularly in the treatment of thrombotic disorders. It works by inhibiting vitamin K epoxide reductase, which reduces the synthesis of active clotting factors in the liver. Historically used in medicine before the rise of warfarin, it is now mainly employed in research settings to study coagulation pathways and enzyme inhibition. Also used in some rodenticides due to its blood-thinning effects in pests.