SELF-MICROEMULSIFYING DRUG DELIVERY SYSTEM

Abstract

<p>ABSTRACT<br />Oral route is the most convenient route of drug administration in many diseases and till today it is the first way investigated in the development of<br />new dosage forms. The major problem in oral drug formulations is low and erratic bioavailability, which mainly results from poor aqueous solubility,<br />thereby pretense problems in their formulation. More than 40% of potential drug products suffer from poor water solubility. For the therapeutic<br />delivery of lipophilic active moieties (biopharmaceutical classification system Class II drugs), lipid-based formulations are inviting increasing<br />attention. Currently, a number of technologies are available to deal with the poor solubility, dissolution rate, and bioavailability of insoluble drugs.<br />One of the promising techniques is self-microemulsifying drug delivery systems (SMEDDS). SMEDDS have gained exposure for their ability to increase<br />solubility and bioavailability of poorly soluble drugs. SMEDDS, which are isotropic mixtures of oils, surfactants, solvents, and co-solvents/surfactants<br />can be used for the design of formulations to improve the oral absorption of highly lipophilic drug compounds. Conventional SMEDDS are mostly<br />prepared in a liquid form, which can have some disadvantages. SMEDDS can be orally administered in soft or hard gelatin capsules and form fine<br />relatively stable oil-in-water emulsions. Solid-SMEDDS are prepared by solidification of liquid/semisolid self-micron emulsifying ingredients into<br />powders, have gained popularity. This article gives a complete overview of SMEDDS, but special attention has been paid to formulation, design,<br />evaluation, and little emphasis on application of SMEDDS.<br />Keywords: Self-microemulsifying drug delivery system, Surfactant, Oil, Co-surfactant, Bioavailability, Lipophilic, Biopharmaceutical classification<br />system Class II drugs.</p>