ABSTRACT
Oral controlled release and site specific drug delivery system has been of great interest in pharmaceutical field to achieve improved therapeutic advantage. Concept of novel drug delivery system arose to overcome certain aspect related to physicochemical properties of drug molecule and the related formulations. Gastro retentive drug delivery system is one of such novel approaches to prolong gastric residence time, thereby targeting site specific drug release in the stomach for local or systemic effects. This approach is useful particularly for the drugs which have narrow absorption window in the upper part of gastro intestinal tract. In this review we have been discussed various approaches of gastro retentive drug delivery system, such as floating and non-floating systems.