ABSTRACT
The aim of this study was to develop a single combined once-daily sustained releasemicroencapsulated dosage form of Allopurinol and Nimesulide using Ethyl cellulose as releasecontrolling factor and to evaluate drug release parameters as per various release kinetic models. Inorder to achieve required sustained release profile, microparticles were prepared using coacervationthermal change technique. The formulated microparticles were also characterized by physical andchemical parameters and results were found in acceptable limits. Different dissolution models wereapplied to drug release data in order to evaluate release mechanisms and kinetics. The drug releasedata fit well to the Higuchi expression. Drug release mechanism was found as a complex anomalousone(AU)
