Design and Development of Solid Dispersions of Simvastatin for Enhancing the Solubility

  The aim of the present work was to improve the solubility and dissolution rate of simvastatin, a drug used for the treatment of hyperlipidemia. Simvastatin is a selective competitive inhibitor of HMG CoA reductase. However its absolute bioavailability is 5 %. To increase the solubility of drug solid dispersion was prepared. Solid dispersion preliminary solubility analysis was carried out for the selection of carriers and solid dispersion was prepared with PEG 4000 and PVP-K30. These solid dispersions were analyzed for the solubility and In-vitro dissolution profile, solid dispersion of drug with PEG 4000 had shown enhanced solubility with improved dissolution rate. Further FTIR, X-Ray studies were carried out. Solid dispersion prepared with PEG 4000 in 1:5 ratio shows the presence of amorphous form confirmed by the characterization study .The study also shows the that dissolution rate of Simvastatin can be enhanced to considerable extent by solid dispersion technique with PEG4000. Key words: Hyperlipidemia, solid dispersion, PEG4000, PVP-K30.