Prednisone for chronic active liver disease: pharmacokinetics, including conversion to prednisolone.

To determine the effect of impaired liver function on conversion of prednisone to prednisolone, and to investigate the relationship of this to responses to treatment with prednisone, we measured serum prednisone and prednisolone by radioimmunoassay after 10 mg of prednisone was given by vein to 10 healthy volunteers, 6 untreated patients with severe chronic active liver disease (CALD), 10 patients with prednisone-induced remission of CALD, and 3 patients with CALD deteriorating despite treatment with prednisone. Prednisone disappearance was comparable in all groups and substantial values for serum prednisolone appeared in all groups within 0.3 hr. Minor differences between the groups included lower than normal serum prednisolone in severe CALD and treatment failure; a higher percentage of nonprotein bound prednisolone in such patients; and an association between earlier treatment with prednisone and an increased disappearance rate of prednisolone. We conclude that no major defect of prednisone metabolism occurs in CALD and that failure of this condition to respond to therapy with prednisone is caused by other factors.