FORMULATION AND EVALUATION OF ORAL SUSTAINED RELEASE DRY SUSPENSION OF METFORMIN HYDROCHLORIDE

Vivek V. Nalawade*, Dr. Ashok L. Peepliwal, Dr. Supriya S. Shidhaye, Anuradha Mhadgut, Swasti Pandey

ABSTRACT

The developed formulation aim was to overcome the problem with Metformin HCl sustained release tablets like difficulty in swallowing due to large tablet size and elimination of intact tablet in the stools resulting in patient incompliance. Hence multiparticulate sustained release drug delivery system to be converted to a liquid oral formulation was developed for patients of Type 2 diabetes. The developed formulation will also be beneficial for patients of Type 2 diabetes suffering from dysphagia, stroke, difficulty in swallowing, geriatric patients etc. These patients may consume it easily and long term therapy may be maintained. A sustained release dosage form of Metformin HCl in the form of microspheres was prepared by solvent evaporation method using polymers Ethyl Cellulose and EUDRAGIT® S 100. Optimization of the factors like Drug to Polymer and the Polymer to Polymer ratio was done using a 22 factorial design. The trials were designed using Drug to polymer ratio and Polymer to Polymer ratio as the two factors at 2 levels. The resulting microspheres were evaluated for entrapment efficiency, drug loading and percent yield of the process and dissolution profile. The solutions obtained by this optimization were converted in to a dry sustained release ready to use suspension and also compared with the marketed formulation.

Keywords: Metformin HCl, Ethyl cellulose, EUDRAGIT® S 100, Sustained release, Solvent evaporation, Factorial design, Dry sustained release suspension.