What exactly is warfarin?

What exactly is warfarin?

Warfarin (also known under the brand names Coumadin, Jantoven,  Marevan, Lawarin, Waran, and Warfant) is an anticoagulant normally used  in the prevention of the formation of blood clots in the blood vessels and their migration  elsewhere in the body respectively.              It was initially introduced in 1948 as a pesticide against rats and mice              In the early 1950s warfarin was found to be effective and relatively safe for  preventing abnormal formation and migration of blood clots in many disorders  (such formations may lead to heart attacks or strokes). It was approved for use as a  medication in 1954 and has remained popular ever since; warfarin is the most widely  prescribed oral anticoagulant drug in North America.             Despite its effectiveness, treatment with warfarin has several shortcomings.  Many commonly used medications interact with warfarin, as do some foods (particularly  leaf vegetable foods or "greens," since these typically contain large amounts of vitamin K)  and its activity has to be monitored by blood testing for the international normalized ratio  (INR) to ensure an adequate yet safe dose is taken.               A high INR predisposes to a high risk of bleeding, while an INR below the therapeutic  target indicates that the dose of warfarin is insufficient to protect against abnormal  formation and migration of blood clots.               Warfarin is used to decrease the tendency for thrombosis or for prevention of  further episodes in those individuals that have already formed a blood clot (thrombus).  Warfarin treatment can help prevent formation of future blood clots and help reduce the  risk of migration of a thrombus to a spot where it blocks blood supply to a vital organ.             Warfarin is best suited for anticoagulation (clot formation inhibition) in areas of  slowly running blood (such as in veins and the pooled blood behind artificial and natural  valves) and in blood pooled in dysfunctional cardiac atria.  Thus, common clinical indications for warfarin use are atrial fibrillation, the presence of  artificial heart valves, deep venous thrombosis, and pulmonary embolism (where the  embolized clots first form in veins). Warfarin is also used in antiphospholipid syndrome.  It has been used occasionally after heart attacks (myocardial infarctions), but is far less  effective at preventing new thromboses in coronary arteries. Prevention of clotting in  arteries is usually undertaken with antiplatelet drugs, which act by a different mechanism f rom warfarin (which normally has no effect on platelet function). (the above was taken from Wikipedia at http://en.wikipedia.org/wiki/Warfarin).  The items above in italics and the underlined emphasis, I have added) Just for interest, the molecule of warfarin is shown below! The name warfarin stems from its discovery at the University of Wisconsin,  incorporating the acronym for the organization which funded the key research  (WARF, for Wisconsin Alumni Research Foundation).