ABSTRACT
The discovered new chemical entities have high lipophilicity and poor aqueous solubility (Biopharmaceutics Classification System class II and IV) which result in poor oral bioavailability, lack of dose proportionality, and high intra- and intersubject variability. For better therapeutic regimen, solubility is the most imperative criterion to achieve desired concentration of drug in systemic circulation. Self-nanoemulsifying drug delivery system (SNEDDS) is an emerging novel technique which solves problems associated with the delivery of poorly soluble drugs. They are isotropic mixture of oil, surfactant, and cosurfactant and are vital tool in solving low bioavailability issue of poorly soluble drug. The technique involved encapsulation of drug in a lipid base with or without pharmaceutically acceptable surfactant. Very recently, the technique has attracted researchers and industries owing to their physical stability, easy manufacturing methods, and can be filled in soft gelatin capsules. On administration of SNEDDS, it generates a drug containing microemulsion with a large surface area upon dispersion in the gastrointestinal tract. The emulsions facilitate the absorption of the drug via intestinal lymphatic pathway and by partitioning of drug into the aqueous phase of intestinal fluids, which results in higher 242bioavailability of the drug. The present chapter deals with the formulation components, mechanism of self-emulsification, formulation methodology, evaluation parameters, and application of self-microemulsifying drug delivery system.
