FORMULATION AND IN-VITRO EVALUATION OF GASTRO RETENTIVE BILAYER FLOATING TABLET OF FAMOTIDINE HYDROCHLORIDE

The present study aims to formulate bilayered tablets of famotidine hydrochloride with a fast release layer using sodium starch glycolate, cross povidone and a sustaining floating layer using polymers like HPMC K100M and HPMC K15M by effervescent approach. The release characteristics were studied on the basis of gel forming polymer, methocel with different concentration of citric acid and sodium bicarbonate. The in vitro buoyancy and floatability were found to be optimum in combination of sodium bicarbonate, citric acid and methocel at concentration of 13 mg, 6 mg and 90 mg respectively. The drug release from floating tablets was found to be 93.87% for F1 with methocel K15M. The drug release was sustained for a period of 20-24 hours. When compared different grades of methocel (K100M and K15M), the methocel K15M (low viscosity grade) provided better-sustained release characteristics with excellent in vitro buoyancy. The IR study reveals that there is no any possible interaction between drug and excipients used for such formulation. The data from release studies were fitted in different models viz. zero order, first order and Korsemeyer’s equation. The result indicated the coupling of swelling and diffusion mechanism so called as Fickian diffusion of famotidine from floating tablets. Keywords: Bilayered tablets, Fast release layer, Floating layer, Polymers: HPMC, K100M, HPMC K15M, Methocel, Citric acid, Sodium bicarbonate, Famotidine hydrochloride