Basics of Self Micro Emulsifying Drug Delivery System

About 70-75% of drugs is taken orally and is found not to be as useful as desired. A self-micro emulsifying drug delivery system (SMEDDS) is a drug delivery system that uses a micro-emulsion achieved by chemical rather than mechanical means. Micro-emulsions have significant potential for use in drug delivery, and SMEDDS are the best of these systems. SMEDDS are of particular value in increasing the absorption of lipophilic drugs taken orally. SMEDDS are mixtures  of natural or  synthetic oils,  solid  or  liquid  surfactants, or alternatively, one or more  hydrophilic solvents and  co-solvents/surfactants  that have a unique ability  of  forming fine  oil-in-water (o/w) micro  emulsions  upon mild agitation followed  by  dilution in  aqueous media, such as  GI fluids. SMEDDS spread readily in the GI tract, and the digestive motility of the stomach and the intestine provide the agitation necessary for self-emulsification. SMEDDS can be encapsulated in hard or soft gelatin capsules or can be converted to solid state (Solid SEDDS/SMEDDS). This review article provides an overview of SMEDDS and its advantages over conventional dosage forms. Keywords: SMEDDS, Micro-emulsions, Co-solvent