DEVELOPMENT OF GASTRO-RETENTIVE FLOATING MICROSPHERES OF ONDANSETRON HYDROCHLORIDE

Ondansetron hydrochloride (OND) is indicated for prevention of nausea and vomiting during chemotherapy. Due to its insolubility in intestinal pH, it is absorbed only in the stomach. In the present study, an attempt was made to increase gastric retention time of ondansetron hydrochloride by preparing its floating microspheres by solvent evaporation method with ethyl cellulose (EC) and hydroxypropylmethylcellulose (HPMC). Microspheres were characterized for percentage yield, particle size, surface morphology, floating behaviour, entrapment efficiency and in vitro release. Polymer ratio and stirring speed seemed to have significant impact on size, entrapment efficiency, floating time and release profile. Hydroxypropylmethylcellulose: ethyl cellulose in the ratio 1: 3, gave most suitable buoyancy and drug release. By increasing polymer concentration, the mean particle size of microspheres increased while drug release rate decreased. Developed formulation of ondansetron hydrochloride can be used for prolonging its retention in the stomach for at least 12 hrs, thereby improving bioavailability and patient compliance.