Formulation and dissolution kinetics of fast-release glibenclamide tablets

Background: Glibenclamide is oral antidiabetic drug that belongs to a class of medications known as sulfonylureas. It is indicated for the treatment of Type II non-insulin-dependent diabetes. Aim: The purpose of this work was to improve the dissolution of glibenclamide by utilizing solid dispersion technology. Materials and Methods: Glibenclamide was dispersed in water-soluble polymers; polyethylene glycol (PEG) 6000, and polyvinylpyrrolidone (PVP) using fusion and solvent method, respectively. The solubility and dissolution kinetics of solid dispersions were studied. Results: The effect of various drug:polymer ratios on the equilibrium solubility of glibenclamide was evaluated. The solubility increased as the amount of polymers was increased. Glibenclamide-PVP solid dispersion showed a threefoldincrease in the solubility of glibenclamide as compared to glibenclamide-PEG solid dispersion. The dissolution of dispersed glibenclamide was diffusion-controlled. The hydrodynamic layer thickness is influenced by the stirring rate. The data indicated that increasing the stirring rate decreased the thickness of the hydrodynamic layer. Tablets with an improved dissolution profile as compared to commercial product Euglucon® tablets were prepared. Conclusions: The solubility and dissolution profiles of glibenclamide were improved by solid dispersion technology. This may lead to enhancement of the bioavailability and efficiency of the drug.