Isolation, characterization and direct estimation of dazoxiben and its glucuronide from human plasma and urine.

1. The major metabolite of dazoxiben in human urine was isolated by XAD-2 and silica chromatography, then identified as a glucuronide conjugate by mass spectrometry and n.m.r. spectroscopy. 2. Levels of dazoxiben and the metabolite in plasma were measured by extraction onto activated charcoal, followed by h.p.l.c. analysis. 3. The method has been used to determine the pharmacokinetics of the drug and metabolite, after intravenous and oral administration of single 100 mg doses to man.