Enhancing the Bioavailability of Glipizide by Solid Dispersion

Solid dispersion of glipizide were prepared using water soluble carriers such as polyethylene glycol and polyvinylpyrrolidone by melting and solvent evaporation method in an attempt to increase the dissolution rate of glipizide, a practically insoluble drug in water. Differential scanning calorimetey, xray diffractometry and in vitro dissolution studies were used to characterize the solid dispersion. No chemical interaction was found between glipizide and polyethylene glycol/polyvinylpyrrolidone. The result from differential scanning calorimetey and x-ray diffractometry studies shows that polyethylene glycol/polyvinylpyrrolidone inhibits the crystallization of glipizide. The solid dispersion prepared in this study was found to have higher dissolution rates compared to pure glipizide and physical mixture of glipizide with polyethylene glycol and glipizide with polyvinylpyrrolidone.