COMPARATIVE PHARMACOKINETICS AND BIOAVAILABILITY OF 2 COTRIMOXAZOLE PREPARATIONS

The objective of this study was to assess both pharmacokinetic propert ies and bioavailability of a newly developed cotrimoxazole preparation (Bioprim(R) tablets, 80 mg of trimethoprim/400 mg sulfamethoxazole), in comparison with a reference preparation commercially available (Bac trim(R) tablets, 80 mg of trimethoprim/400 mg of sulfamethoxazole). Th e pharmacokinetics and bioavailability of cotrimoxazole from these pre parations were compared in an open randomized crossover study in 12 he althy males. Plasma concentrations of trimethoprim and sulfamethoxazol e were measured by HPLC after protein precipitation. Noncompartmental pharmacokinetic analysis was performed on the plasma concentration-tim e data. The obtained pharmacokinetic values (C-max, t(max), beta, t(1/ 2)(beta), CL, V-d, AUC36, AUC(infinity)) of both trimethoprim and sulf amethoxazole determined in our study agreed with values reported in th e literature. Westlake's and Nonparametric probability tests with the 90% confidence intervals, for both trimethoprim and sulfamethoxazole g ave the differences within 80 and 120%, for all necessary measures (C- max, t(max) and AUC(infinity)). Statistical analysis of the data has s hown that the preparations have similar pharmacokinetic profiles and t herefore can be considered equally bioavailable.