FORMULATION AND EVALUATION OF BILAYER TABLET OF GLYBURIDE AND METFOMIN

The purpose of this study was to develop a bilayer antidiabetic tablet of Metformin as sustained release and Glyburide as immediate release. In sustained release formulation there was two polymers were used such as HPMC K4M and HPMCK200M and in immediate release formulation there was also two super disintegrants are used such as Croscarmellose and Sodium Starch Glycolate were used. The bilayer formulation was prepared by direct compression method.Type and concentration of super disintegrant among [Sodium Starch Glycolate (SSG)/Croscarmellose] was optimized to enhance the dissolution rate (DR) of Glyburide from the IR layer of BT. Type and concentration of SR polymer among (HPMC K4M / HPMC K200M) was optimized to extend the release of Metformin HCl up to 12 h profile from the SR layer of BT. It was concluded that the optimization of the ratio of Glyburide: Metformin HCl SR polymer (HPMC K200M), had significant effect on extending the release profiles of Metformin HCl. The ratio of Metformin HCl: HPMC K200M at forms a better matrix for the extending the release of Metformin HCl up to 12 h from the SR layer of BT. The optimized formulation: BT6 [IR6 (15% w/w Sodium Starch Glycolate as super disintegrant and SR6 (HPMC K200M as SR polymer)] releases 97.62% of Glyburide from the IR layer within 40 min and extends the release of Metformin HCl up to 12 h with a better release profile. It passes the accelerated stability studies as per ICH guidelines. A combination of these two classes [(Biguanides)(Metformin HCl) and (Sulfonyl urea) (Glyburide)] of glucose-lowering agents and formulating them as a BT is more effective in the treatment and maintenance of type 2 diabetes mellitus.