Biopharmaceutical classification system

Drugs belonging to BCS class II, low solubility and high permeability; undergo dissolution-rate limited gastrointestinal absorption. Glimepiride is one of the famous drugs belonging to BCS class II. Its poor aqueous solubility usually causes poor dissolution and unpredicted bioavailability. Hence, formulation techniques that accelerate drug dissolution can guarantee a parallel improvement in bioavailability. Now a days different techniques are available to enhance the solubility of drug like co-solvent, solid dispersion, chemical modification of drug, liquisolid technique etc. One of the favorable strategy to improve the solubility and hence bioavailability of poorly water soluble drugs is theformulation of solid dispersion. The solid dispersion may be prepared by solvent evaporation method, melting method, melt solvent method, kneading method, co-grinding method, co-precipitation method, modified solvent evaporation method, spray drying, gel entrapment techniqueand co-precipitation with supercritical fluid. This review article comprises of the research materialized in the field of solubility and dissolution enhancement of glimepiride.