The Value of Plasma-Warfarin Measurement
For the last 30 years I have measured the plasma concentration of warfarin in man and animal and correlated it with the pharmacologic effect (O’Reilly, 1986). This effect of oral anticoagulants like warfarin is measured by the one-stage prothrombin time in plasma, which is easily quantitated. In the therapeutic monitoring of oral anticoagulants, the prothrombin time must be utilized and not the blood concentrations of the drug. Both the therapeutic efficacy and the clinical safety of these drugs in patients is achieved only by the careful control of the prothrombin time within narrow limits. The correlation of the plasma concentration of warfarin and the prothrombin-time response has yielded insights on the clinical use of racemic warfarin. For each of the entities described herein, the tables of data and the illustrations may be found in the original publications cited in the references.
KeywordsNormal Human Subject Autosomal Dominant Transmission Metabolic Disposition Racemic Warfarin Warfarin Resistance
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