RECENT FRONTIERS IN SELF MICRO EMULSIFYING DRUG DELIVERY SYSTEM: A REVIEW

Oral route has always been the preferred route of drug administration in many diseases. This route is limited to those drugs molecules that are permeable across the gastric mucosa and are sparingly soluble. Solubility is an important parameter to achieve the desired concentration of drug in systemic circulation for therapeutic response. As a consequence of modern drug discovery techniques, there has been a steady increase in the number of new active lipophilic compounds that are poorly water-soluble. It is a challenge for a scientist to convert those molecules into an orally administered formulation with sufficient bioavailability. Improving oral bioavailability of poorly water-soluble drugs using self micro emulsifying drug delivery systems (SMEDDS) appears most promising. Currently, various technologies are available to deal with insoluble drugs such as micronization, solid dispersions, complex formation, etc. Among the several approaches, SMEDDS has emerged as a distinctive approach used to improve the bioavailability of hydrophobic drugs. SMEDDS is isotropic mixture of drug, surfactants, cosurfactants, and oil which have unique ability to form fine o/w microemulsion on slight shaking followed by dilution with gastrointestinal fluid. In-vitro features such as concentration of surfactants, ratio of oil to surfactant, zeta potential, and size of droplet play a crucial role in drug absorption orally. The present article compiled comprehensively which gives a complete overview of SMEDDS as a promising approach to effectively tackle the problem of poorly soluble molecules. It also provides a discussion on recent developments in SMEDDS and solid SMEDDS, their characterization and applications.