RESUMO
The pharmacokinetics of oral ranitidine were studied in 24 Mexican male healthy volunteers. Subjects received a tablet containing 150 mg of ranitidine (Azantac, Glaxo de México, Mexico City) after an overnight fast and blood samples were drawn at several times for a period of 24 h. Ranitidine concentration in plasma was measured by high performance liquid chromatography and pharmacokinetic parameters were determined by non-compartmental analysis. Ranitidine plasma concentration increased with time, reaching a maximum of (mean +/- SEM) 484 +/- 34 ng/ml in 2.7 +/- 0.2 h. Plasma levels then decayed with a terminal half-life of 4.8 +/- 0.3 h. The area under the plasma concentration against time curve was 2440 +/- 126 ngh/ml. Oral ranitidine pharmacokinetic parameters in Mexicans appeared to be similar to those previously reported for Caucasians.
Assuntos
Ranitidina/farmacocinética , Administração Oral , Adulto , Cromatografia Líquida de Alta Pressão , Etnicidade , Meia-Vida , Humanos , Masculino , México , Ranitidina/administração & dosagem , Ranitidina/sangue , ComprimidosRESUMO
Eighty-six Mexican young healthy volunteers received a 500-mg oral sulfamethazine dose. Urine was collected 0--6 h after medication and acetylated, and unchanged sulfamethazine were determined by the Bratton--Marshall method. The frequency distribution of acetylated/unchanged sulfamethazine, determined by probit analysis, appeared to be trimodal, allowing the discrimination of three acetylator phenotypes. The frequencies of rapid, intermediate, and slow acetylators were 28%, 42%, and 30% respectively, being consistent with the Hardy-Weinberg law.