Pharmacokinetics of fluocortolone in man.

The kinetics of the synthetic corticoid fluocortolone was determined in 9 healthy female volunteers after a single oral dose of 20 mg. The maximal plasma level fluocortolone (Cmax) of 202 +/- 70 ng/ml occurred within 85 +/- 32 min of oral intake after which it declined monoexponentially. Total plasma clearance was 6.48 +/- 2.07 ml/min X kg and the clearance of unbound fluocortolone was 60.38 +/- 26.67 ml/min X kg. Plasma protein binding was 83 to 95%. The volume of distribution at steady-state was 1.01 +/- 0.341/kg for total fluocortolone and 11.21 +/- 3.771/kg for unbound drug. The results of the study characterize the kinetics of unbound fluocortolone for the first time. In addition, the kinetics of total fluocortolone presented here confirm values calculated previously.