title: [Antacid activity of citrate-bicarbonate complex of effervescent formulations of ranitidine. In vitro analysis using 'artificial stomach-duodenum' model].
abstract: Antacid activity supported by citrate-bicarbonate complex of four effervescent ranitidine forms has been assessed in vitro using an 'artificial stomach-duodenum' model controlled by microcomputer. This model allows (i) maintenance of constant the rates of the fluxes throughout the experiments or (ii) simulation of gastroduodenal flux regulation, in the normal subject (NS) or in the duodenal ulcer patient (DU) situation. The four forms developed a theoretical maximal antacid capacity between 61 and 81 mmol with a maximum intragastric pH between 3.2 and 4.8. In the gastroduodenal flux regulation simulation, antacid activity duration was rapid and included between 85 and 118 min in NS situation (50 to 56 mmol H+ consumed) and between 75 and 93 min in DU situation (43 to 47 mmol H+ consumed). The reduction of acid load penetrating into the duodenum was contained between 36 and 50 per cent. Effervescent compounds exerted a neutralising activity and a buffering capacity close to pH 6.0 (5 per cent of total antacid capacity), related to antacid potency.
authors: Département de Pharmacie Clinique, Faculté de Pharmacie, Châtenay-Malabry, France.
authors: J
authors: J
authors: Vatier
authors: S
authors: S
authors: Cai
authors: A
authors: A
authors: Slama
authors: R
authors: R
authors: Farinotti
mesh_terms: D000863:Antacids / Q000008:administration & dosage* / Q000494:pharmacology; D001639:Bicarbonates / Q000008:administration & dosage* / Q000494:pharmacology*; D002951:Citrates / Q000008:administration & dosage* / Q000494:pharmacology*; D003198:Computer Simulation; D004338:Drug Combinations; D004386:Duodenum / Q000502:physiology; D066298:In Vitro Techniques; D011899:Ranitidine / Q000008:administration & dosage / Q000737:chemistry; D013270:Stomach / Q000502:physiology; D013607:Tablets
chemical_list: D000863:Antacids; D001639:Bicarbonates; D002951:Citrates; D004338:Drug Combinations; D013607:Tablets; D011899:Ranitidine
vernacular_title: Activité antiacide du couple citrate-bicarbonate des formes effervescentes de ranitidine. Analyse in vitro à l'aide du modèle de 'l'estomac-duodénum artificiels'.