ORAL BIOAVAILABILITY IMPROVEMENT USING SOLID DISPERSION TECHNIQUES: A REVIEW

A solid dispersion is the dispersion of one or more active ingredients in an inert carrier or matrix at solid state prepared by melting, solvent, or melting-solvent Method. The poor solubility of drug substances in water and their low dissolution rate in the aqueous gastro-intestinal fluids often lead to insufficient bioavailability. If the dissolution rate of the active ingredient in the gastrointestinal liquid is the rate-limiting factor for the absorption of the drug, the objective of the formulation will have to be an increase in the dissolution rate. From many years, variety of solubility techniques have been used & studied for increasing solubility of poorly soluble drugs. Around 40% of chemical entities discovered by pharmaceutical industry are poorly soluble in nature. Solid dispersion is one of these methods, which was most widely and successfully applied to improve the solubility, dissolution rate & bioavailability of the poorly soluble drugs. This article reviews historical background of solid dispersion technology, limitations, classification, and various preparation techniques with its advantages and disadvantages. This review also discusses the recent advances in the field of solid dispersion technology and gives rise to reasoning and suggested choices of carrier or matrix and solid dispersion procedure.