known as warfarin and sold as Coumadin. Cecil’s column this week (not yet on the web)states that a 1983 article in * FDA Consumer * states “there has been no indicaion that coumarin [the generic name of the chemical from which it has been derived] itself produces this blood-thinning effect in humans.” [Under the name warfarin it is used to poison rats by causing internal bleeding.]
Cecil continues that a young woman who drank copious amounts of a home-brew tea contining coumarin suffered abnormal menstrual bleeding.
All that may be well and true, but he should have noted that warfarin (Coumadin) is a well established anticoagulant now. It acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. The resultant effect is a sequential depression of Factors VII, IX, X and XI.