Pharmacokinetics and relative bioavailability of tablet of micronized glibenclamide in 4 Chinese healthy men.

Pharmacokinetic characteristics and relative bioavailability of the regular preparation (RG) and micronized preparation (MG) of glibenclamide (Gli) were studied in 4 Chinese healthy men. Each volunteer entered 2 consecutive experiments at the same dose (10.5 mg) of RG and MG tablets given orally. Blood samples were drawn before and 0.5, 1, 2, 3, 4, 6, 8, 10, and 12 h after po. A selective HPLC method with a uv spectrophotometric detector (sensitivity: 16 ng.ml-1) was established for determining serum Gli concentration. Cmax for RG was 212 +/- 41 ng.ml-1, for MG 529 +/- 73 ng.ml-1. Tmax for RG and MG were 3.5 +/- 0.6 and 2.2 +/- 0.3 h, respectively. The relative oral bioavailability of MG was found to be 77%, increased approximately 1.7-fold that of RG. The other pharmacokinetic parameters (Vd, Cl, T1/2) were substantially the same after ingestion of GR and MG.