Studies on Gastroselective Famotidine Floating Tablets for Gastric Ulcers and Effect of Polymeric Excipients on Drug Release.

Abstract

The present investigation was planned to formulate effervescent floating, gastroretentive guar gum tablets containing famotidine, which can be useful in the treatment of gastric ulcer. The investigations carried out on various formulations resulted in totally four formulations obeying zero order kinetics. The study on rheological characteristics of powder bed indicated that, all the granules were freely flowing and compressible; density of all the tablets was less than 1, thereby assisting in floating of the dosage form on the surface of the simulated gastric fluids in vitro. Studies on compression characteristics indicated that, the tablets float over the surface and remain over the surface for a period of more than 10 h, except FS and FS1, which stay over the surface little lesser time than other tablets. Drug content was fairly uniform and consistent. The floating guar gum tablets containing HPMC K4M and Xanthan gum as binders follow zero order drug release kinetics. The increasing the amounts of magnesium stearate does not significantly alter the drug release kinetics; it improves the flowability of the granule bed. Tablets swell when in contact with water and the swelling index is highest with xanthan gum gel followed by the order, followed by FH> FX1> FC>FH1> FC1>FS>FS1. Stability studies at 45ºC and 75 % RH indicates that there is decrease in drug content, amounting to 30%, when observed for a period of 3 months.

KEYWORDS: Famotidine, Effervescent gastroretentive tablet, Release kinetics, Stability studies