BUOYANT SYSTEMS: A NOVEL APPROACH TOWARDS GASTRORETENTIVE DRUG DELIVERY SYSTEMS
In recent era various technological attempts have been made in the research and development of controlled release oral drug delivery systems to overcome physiological adversities, such as short gastric residence times (GRT) and unpredictable gastric emptying times (GET). One of the potential approaches in the area of oral sustained release drug delivery is gastroretentive drug delivery system (GRDDS). Drugs having a narrow absorption window and having good solubility in gastric fluids are quickly eliminated from stomach due to rapid gastric transit. GRDDS prolongs the retention time of dosage forms in the stomach or upper part of gastro intestinal tract (GIT), so it enhances solubility, ultimately bioavailability of drugs and therapeutic efficacy of the dosage form. Several methodologies have been implemented to increase the gastric residence time of dosage forms, such as buoyancy or floating system, hydrodynamically balanced system, expanding or swelling systems, bio/mucoadhesive system, sedimentation or high density system, geometry or modified shape system. This paper aims to review the current & recent developments of Stomach Specific floating drug delivery systems to provide basic principles useful to circumvent the difficulties associated with formulation design.