Kinetics and metabolism of sulfinpyrazone.
Six normal subjects (three men and three women) took 200 mg sulfinpyrazone in two oral preparations, a capsule and a suspension. Plasma and urine levels of sulfinpyrazone and the sulfide, p-hydroxy, and sulfone metabolites were measured over three days. The plasma sulfinpyrazone/time concentration profiles indicated a postabsorptive biexponential decline with a mean terminal half life (t1/2) of 299 +/- 107 min. There was intersubject variation in the formation of the metabolites, the greatest being with the sulfide metabolite. Mean t1/2 of the sulfide metabolite was 659 +/- 192 min. The apparent fraction of sulfinpyrazone absorbed was 0.93 +/- 0.24 and the free fraction in plasma was 1.26 +/- 0.04%. Since the sulfide metabolite has a more potent antiplatelet effect and its formation in normal subjects is variable, direct administration of the sulfide may provide a more predictable antithrombotic effect in patients.
D000042:Absorption; D000328:Adult; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006207:Half-Life; D006801:Humans; D007700:Kinetics; D008297:Male; D012044:Regression Analysis; D013442:Sulfinpyrazone / Q000097:blood / Q000378:metabolism*
D013442:Sulfinpyrazone