Volume 2

October-December 2010

A review on key parameters and components in designing of osmotic controlled oral drug delivery systems

N B Khavare, Fatima S Dasankoppa, N G Najundaswamy

During the past three decades significant advances have been made in the area of controlled drug delivery. In a typical therapeutic regimen, the drug dose and the dosing interval are optimized to maintain drug concentration within therapeutic window, thus ensuring efficacy while minimizing toxic side effects. Surveys indicated that dosing more than once or twice daily greatly reduces patient compliance. Hence, the primary objective for controlled drug release is to deliver a pharmacologically active agent in a predetermined, predictable and reproducible manner. Numerous technologies have been used to control the systemic delivery of drugs. One of the most interesting systems employs osmotic pressure as a source of energy. Drug delivery from osmotically controlled oral drug delivery systems (OCODDS), to a large extent, is independent of the physiological factors of the gastrointestinal tract and these systems can be utilized for systemic as well as targeted delivery of drugs. The release of drug(s) from osmotic systems is governed by various formulation factors such as solubility and osmotic pressure of the core component(s), size of the delivery orifice, and nature of the ratecontrolling membrane. By optimizing formulation and processing factors, it is possible to develop osmotic systems to deliver drugs of diverse nature at a preprogrammed rate. In the present review, various types of osmotically controlled oral drug delivery systems, osmosis and mechanism of osmotic controlled release, release kinetics, key parameters that influence the design of osmotic controlled drug delivery systems and critical formulation factors are discussed.

Keywords: Osmotically Controlled Oral Drug Delivery Systems, Osmosis, Release Kinetics, Formulation Factors.