ANTIHYPERLIPIDIMIC GASTRO FLOATING TABLET OF PRAVASTATIN PREPARED FROM DIFFERENT GRADES OF HPMC POLYMER

Oral route is the most convenient route for the drug delivery because of ease of administration, economic therapy & patient compliance. Floating drug delivery system (FDDS) is one of the convenient ways than the convectional oral drug administration which keep drugs buoyant is stomach due to their low density than gastric fluid and can be a potential candidate for controlled release of drug over an extended period of time. FDDS are expected to maximize the absorption resulting in enhanced bioavailability and prolong residence time of drug in stomach. Pravastatin is an oral hyperlipidemic drug used to reduce blood cholesterol level. Floating tablets of pravastatin were prepared by using direct compression technique. The floating tablets of Pravastatin were prepared with different viscosity grades of HPMC (HPMC K4M, HPMC K15M, and HPMC K100M) and with different drug to polymer ratios. Prepared tablets were evaluated for parameters like friability, hardness, thickness, percentage weight variation, and content uniformity, buoyancy floating lag time, stability studies and in vitro release. Tablets of all formulations were found to be circular with no cracks and were white to off white in colour. The diameter of all formulations ranged between 7.96 to 8.00mm and thickness was in the range of 2.95 to 3.22mm. Stability Studies were carried out at room temperature for 30 days. The physical stability was assessed by the appearance and there was no change in colour or shape of the tablet on storage. F9 formulation containing 80 mg of HPMC K100M was most stable at the end of storage period. Thus, from the results of tablet evaluation it can be concluded that due to the buoyancy of drug in stomach, the prepared pravastin floating tablet maximize the absorption resulting in enhanced bioavailaibility and prolong resident time of drug in stomach. Key words: Buoyant tablets, Gastroretentive, floating tablets, pravastatin, sustained release tablets