Pharmacokinetics of piroximone (MDL 19.205) in healthy volunteers

Six healthy, male subjects received single intravenous and oral doses of piroximone. Plasma piroximone concentrations were assayed up to 8 h after each dose by HPLC. Urinary excretion of the parent compound was also determined. Following the oral dose, piroximone reached peak plasma concentrations within 30 to 90 min. The t1/2 of the terminal decay phase was 2.8 h, the mean apparent volume of distribution was 2.5 l/kg, and the mean total body clearance was 755 ml/min. Mean urinary recovery of parent drug within 24 h was 50% after the intravenous dose and 41% after the oral dose. Renal clearance accounted for approximately 50% of total body clearance. Oral bioavailability, estimated from AUC or urinary recovery, was 80%.