Abstract
The aim of current review was to elaborate the osmotic drug delivery system for controlled release of drugs. The oral route is the most common and most acceptable route of drug administration. For treatment of chronic diseases repeated dose administration is required, the osmotic drug delivery system serve as a tool for control release of drugs in these condition and avoid the repeated administration. The present review illustrates the basics of osmotic drug delivery system, types with special focus on controlled porosity osmotic pump, mechanism of osmosis, ideal drug candidate, formulation techniques, various osmotic agents, pore formers, coating materials and marketed preparation based on osmotic drug delivery system. These parameters may be helpful in designing of dosage for modification in release of various drugs having problem in conventional form.