NOVEL SELF-NANOEMULSIFYING DRUG DELIVERY SYSTEMS (SNEDDS) FOR ORAL DELIVERY OF LIPOPHILIC DRUGS

The self-nanoemulsifying drug delivery system (SNEDDS), is a promising Drug Delivery System which is well known for its prospective to improve the aqueous solubility and oral absorption of poorly water soluble drugs (Pouton, 2000). SNEDDS is an isotropic mixture comprising oil, surfactant, co-surfactant and drug that form oil in water emulsion in aqueous environment under placid agitation. It can readily disperse in the aqueous environment of the gastrointestinal tract to form a fine oil-in-water emulsion with a droplet size not exceeding 100 nm under mild agitation for improving the oral bioavailability of poorly water-soluble drugs (Shah et al., 1994; Constantinides, 1995). Compared to conventional metastable emulsions, SNEDDS is a thermodynamically stable formulation with high solubilization capacity for lipophilic drugs, and also can be filled directly into soft or hard gelatin capsules for convenient oral administration. The Self nano-emulsifying Drug Delivery System (SNEDDS) is applicable on BCS Class II and Class IV Drugs for improving water Solubility of poorly water soluble drugs. It is important to prevent the interfacial tension and improving the dissolution as well as absorption rate of drug molecule. It is the novel drug delivery system which is applicable for parenteral, ophthalmic, intranasal and cosmetic delivery of drugs. The review presents an overview of design of formulation, preparation of components, mechanism of self nano emulsification, biopharmaceutical aspects, characterization methods and applications of self nano-emulsifying drug delivery system (SNEDDS) for enhancement of oral bioavailability of poorly water soluble drugs.