The purpose of this study is to develop gastro-retentive swellable tablets for Ranitidine HCl to improve its bioavailability by delaying gastric residence time with the aid of gastro-protective agent. Eight different batches were prepared with varied concentration of polymers like HPMC, sodium alginate and agar by direct compression. Tablets were then, evaluated for weight variation, hardness, friability, thickness and diameter, swelling index and in vitro drug release in 0.1N HCl. Among formulations, N4, containing HPMC K15 (15%) and sodium alginate (10%), was selected as an optimized formulation due to its complete release (99.73 %) and significant swelling (197%) after 6hr. Further, N4 was subjected to kinetic modeling which showed that N4 followed Korsmeyer-peppas model with R² value of 0.9735 and the value of n (0.316) depicted that the release of ranitidine HCl from swellable matrix was entirely based on diffusion mechanism.
Keywords: Gastroretentive drug delivery, Ranitidine tablet, HPMC K15, Agar, Sodium alginate.