ABSTRACT
About 40% of the drug candidates have poor water solubility due to their low bioavailability. Self-emulsifying drug delivery systems (SEDDs) are mixtures of oils, surfactants and co-surfactants, which efficiently improve dissolution and bioavalabilty of sparingly soluble drugs by rapid self-emulsification. SEDDs belongs to lipid formulations, and size ranges from 100nm (SEDDs) to less than 50nm (SMEDDs). Lipophilic drugs can be dissolved in such systems, enabling them to be administered as a unit dosage form for per-oral administration. When such system is released in the lumen of the gastrointestinal tract, it disperses to form a micro/nano emulsion with the aid of GI fluid. These leads to solubilisation of drug that can subsequently be absorbed by lymphatic pathways, by passing the hepatic first pass effect.