Warfarin

ON the basis of two facts — that bishydroxycoumarin produced a bleeding disease in cattle and that it retarded blood clotting — coumarin compounds were hailed in 1941 as likely antithrombotic agents, a rather debatable prediction on the basis of the facts then available.With the development of the prothrombin-time assay to monitor the drug-induced defect in plasma,1 the stage was set, after a few studies in animals, for the first clinical trials. These studies were reported in 1941, one fifth of a century after "sweet clover disease" was first recognized by Schofield.2 Since World War II, information has accumulated . . .