Compartmental analysis of ranitidine doubled peak plasma profile after oral administration to health volunteers

• Autor(a) principal: Schuck, Virna Josiane Aurelio
• Data de Publicação: 2002
• Outros Autores: Barros, Sergio Gabriel Silva de, Schapoval, Elfrides Eva Scherman, Gruber, Antonio Carlos, Dalla Costa, Teresa Cristina Tavares
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/19556
• topic: Ranitidina; Administração oral; Ensaio clínico controlado; Farmacocinética; Ranitidine; Pharmacokinetics; Compartmental analysis; Double peak plasma profile

The aim of this study was to describe the double peak plasma pharmacokinetic profile of ranitidine after oral administration to healthy volunteers using non-compartmental and compartmental analysis. A single 300 mg dose of ranitidine was given to ten healthy volunteers (5 male and 5 female). Blood samples were drawn at different times and analyzed by HPLC. Plasma profiles were evaluated by non-compartmental and compartmental approaches. The non-compartmental parameters determined were k (0.0054 ± 0.0010 min-1), t1/2 (2.2 ± 0.4 h), Vdss/F (265.3 ± 70.6 L), Cl/F (84.8 ± 24.3 L/h) and AUC (225916 ± 54099 ng*min/mL). The compartmental analysis was carried out using a two compartments body model, with first order absorption from two different sites. The parameters determined were k21 (0.0149 ± 0.0133 min-1), ka1 (0.0117 ± 0.0073 min-1), ka2 (0.1496 ± 0.1699 min-1), Vc (128 ± 75.2 L), a (0.0299 ± 0.0319 min-1), b (0.0074 ± 0.0014 min-1) and time for the beginning of the absorption from the second site (126.7 ± 58.1 min). The model used in the compartmental analysis was adequate to describe the double peak of ranitidine plasma profile and to determine the pharmacokinetic parameters.