Preparation and characterization of solid dispersions of Rofecoxib

The present study is aimed at improving the dissolution of poorly soluble drug, rofecoxib, using solid dispersion technique. The solid dispersions were prepared in different proportions using hydrophilic carriers like mannitol, and urea. The dissolution rate studies were performed in both simulated gastric fluid and simulated intestinal fluid. It is observed that the dissolution was affected by the acidity of the medium. Solid dispersions gave faster dissolution rate when compared to corresponding physical mixture and pure drug. In vivo absorption and anti-inflammatory activity studies of solid dispersions also confirmed the above results. The DSC thermogram and IR spectra revealed that there is no interaction of Rofecoxib with additives and the drug, rofecoxib is stable in solid dispersions.