Formulation and Evaluation of Atorvastatin Calcium Floating Tablets by Using Xanthum Gum as a Release Modifying Agent

Gastroretentive floating controlled drug delivery system containing Atorvastatin calcium was prepared in the form of tablets and evaluating the various processing parameters including the buoyancy studies and in vitro drug release studies in 0.1 N HCl (PH 1.2). Nine formulations containing varying proportions of polymers HPMC K4M, Xanthum gum and fixed amount of Sodium bicarbonate and Citric acid are gas (CO2) forming agents (Sodium bicarbonate are alkalizing agents, Citric acid are Buffering agents), Magnesium stearate Lactose were used as lubricant and diluent respectively. The tablets were prepared by direct compression Method, and the prepared tablets remained buoyant for more than 12 hrs in the release medium. The proportions of the polymers showed significant difference in the release of the drug. Xanthum gum is used as a release modifying agents because it swell and form a gel in acidic medium and which is more stable in acidic medium.