Absolute bioavailability of a new high dose methylprednisolone tablet formulation.

This was a single-blind, single-dose, randomized crossover study to determine the absolute bioavailability of Medrol, a new high dose (100 mg) methylprednisolone tablet product, by comparing it with 100 mg methylprednisolone from an intravenous formulation, Solu-Medrol. Fourteen healthy, non-smoking, Caucasian male volunteers took part. On treatment days volunteers remained recumbent for 4 hours after drug administration, with food and fluid intake standardized over this period. Serial blood samples were drawn over a 14-hour period after drug administration. Plasma methylprednisolone concentrations were determined by high performance liquid chromatography. The geometric means of AUCi.v. and AUCtablet were 4,049 and 3,334 ng.h/ml, respectively. The absolute bioavailability of the tablet product was 82%, which is in agreement with published data for other oral dosage forms of methylprednisolone. Volunteers displayed the expected rise in peripheral blood neutrophil count, but no other clinically relevant changes in hematology or clinical chemistry were observed. No adverse drug reactions were recorded. It is concluded that the tablet product can be used as a substitute for parenteral methylprednisolone in situations requiring high-dose therapy.