Warfarin, also known by the brand names
Coumadin among others, is an
anticoagulant normally used in the
prevention of
thrombosis and
thromboembolism, 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, and is still used for this purpose, although more potent poisons such as
brodifacoum have since been developed. In the early 1950s, warfarin was found to be effective and relatively safe for preventing thrombosis and thromboembolism in many disorders. 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.