ABSTRACT:
Over the years, different formulation technologies intended for gastro retentive dosage delivery were investigated and patented. Oral drug administration has been the predominant route for drug delivery. During the past two decades, numerous oral delivery systems have been developed to act as drug reservoirs from which the active substance can be released over a defined period of time at a predetermined and controlled rate. From a pharmacokinetic point of view, the ideal sustained and controlled release dosage form should be comparable with an intravenous infusion, which supplies continuously the amount of drug needed to maintain constant plasma levels once the steady state is reached. Although some important applications, including oral administration of peptide and protein drugs, can be used to prepare colonic drug delivery systems, targeting drugs to the colon by the oral route. This review article clearly explains the advantages, limitations and need of gastro-retentive drug delivery system. It also covers the various criteria for drugs suitable and not suitable for such delivery. Also, the different types of gastro retentive delivery systems are described with suitable examples.