FORMULATION OF RANITIDINE HYDROCHLORIDE GASTRO RETENTIVE FLOATING TABLET BY USING DIFFERENT RATIO OF POLYMERS

The aim of the present investigation was to develop a novel gastro retentive dosage form of Ranitidine hydrochloride (RHCl) to achieve prolong gastric retention, increase drug bioavailability and to modulate the release of RHCl in the stomach, by using various ratios of HPMC E-15, a low-density grade polymer and it was cheaper and easily available along with Carbopol 934, as gel former. Sodium bicarbonate and citric acid were added as Effervescent agent. The tablets were prepared by wet granulation technique as 12 different formulation batches F1 to F12 depend on variable polymer ratios by using single punch hand operating machine, were evaluated for physical characteristics viz. hardness, swelling index, thickness, and weight variation. Further, tablets were evaluated for in vitro buoyancy time and in vitro release characteristics for 12 hr. Tablet achieved sufficient buoyancy due to the CO₂-gas formation and their entrapment by polymeric gel membrane. The increased amount of a gas forming agent did not affect time to float but increased the drug release from the floating tablets while increasing HPMC matrix content increased time to float and slightly retarded drug release. Formulation batch no. 8 was found to be the best formulation having maximum buoyancy 395 minute and a sustained drug release for 655 minutes. This study indicates that maximum buoyancy and sustained release of drug can be achieved using appropriate combination of gel forming agents and gas generating agents in the formulation of floating tablet. A higher proportion of gas generating agent to gel formatting agent found to be promising for achieving prolong gastric retention and sustained release. The floating tablet offers a simple and practical approach to achieve increased gastric residence time for the dosage form and sustained drug release.