Abstract

FORMULATION AND EVALUATION OF FLOATING OSMOTIC DELIVERY SYSTEM OF CARVEDILOL

Shubham Kundu, Gangadharappa H.V.* and Adithya Pramod

Abstract

Floating osmotic delivery system is a combination of floating and osmotic systems that provides site specific and controlled drug release. Carvedilol is non- selective β blocker under bio pharmaceutical classification system (BCS) class II is widely used in the treatment of hypertension. Half-life of model drug is 6-8 h. The model drug showed promising pharmacokinetics and physico - chemical properties required for controlled releases dosages. Therefore this drug was selected for present investigation. Floating drug delivery system was developed initially by formulating the osmotic core tablet followed by multilayer coating for floating the system. Core tablet comprised of Carvedilol, Mannitol, and sodium bicarbonate which was coated with cellulose acetate (osmotic layer), followed by coating of floating layer with Hydroxyl propyl Methyl cellulose (E15 / E50) and sodium bicarbonate and further coated with entrapment layer composed of Eudragit RL30D.The drug and polymers were characterized by DSC and pre-compression like bulk density, tapped density and Hausner’s ratio. The prepared tablets were evaluated for physical properties like floating lag time, duration of floatation. Invitro studies revealed that drug release depends on concentration of polymer, agitation speed and pH of the medium. From the results, it indicated that formulation were intact. Floating lag time and floating time were dependent on hydroxyl propyl methyl cellulose grade used in floating layer and coating percentage on entrapment layer. Drug release was controlled by changing the amount of mannitol in the core tablets.

Keywords: Sustained release, Matrix tablets, Model drug, Sodium bicarbonate, Hydroxy propyl Methyl cellulose, Eudragit RL 30D,Mannitol, talc.