CURRENT TRENDS IN SOLID DISPERSION: A REVIEW

Abstract

Poor bioavailability of the highly lipophilicdrugs is one major challenges being faced in pharmaceutical industry. Poor absorption of drug from the oral dosage form could be a result of low dissolution rate. Therefore many techniques have been introduced for solubility enhancement out of which Solid Dispersion has attracted considerable interest. Solid dispersion is defined as a group of solid products consisting ofat least two different components, generally a hydrophilic inert carrier ormatrix and a hydrophobic drug. It increases the dissolution rate of highly lipophilic drug which leads to increased solubility and hence bioavailability of the drug. There are various methods of preparation of solid dispersion like fusion method, solvent evaporation, solvent evaporation-deposition, solvent deposition, kneading method, lyophillization, supercritical fluid method.Basically this technique includes a drug with poor aqueous solubility and hydrophilic carrier. Polymers incorporated in solid dispersion technologies are usuallyhydrophilic in nature and also showing compatibility with the drug to enhancethe drug solubility. The present article discusses the basic concept about solid dispersion, various types of solid dispersion, criteria of solvent selection,the methods of preparation, characterization, their advantages, limitations andapplications. Also this reviews about the current trends observed in solid dispersion in past few years and its future prospects