Controlled Porosity Osmotic Tablet

The research work was aimed to formulate a controlled porosity osmotic pump tablets of Diltiazem hydrochloride. The developed extended release formulation delivered a drug for 24 hr. Diltiazem hydrochloride having high solubility and relatively short half- life (3-4.5 hr.) suggest its suitability for an extended formulation. In this developed formulation pores are formed by the incorporation of a leachable component in the coating. Once the tablet comes in contact with the aqueous environment, Subsequently, water diffuses into the core through the microporous membrane, setting up an osmotic gradient and thereby controlling the release of drug. The release rate from these types of systems was dependent on the concentration of osmogen in the tablet core, which generate osmotic pressure difference across the membrane, level of leachable components in the coating and coating thickness. It can be concluded that a controlled porosity osmotic tablet can be successfully formulated using Diltiazem Hcl(120mg), HPMC K100 M(100mg), PEG400(24%) with mannitol(3.5%w/v) for thick coating giving 6% weight gain on coating Along with other convetional tablet.