Abstract
Hydrodynamically balanced drug delivery systems have great potential as controlled-release drug delivery systems. They allow increased penetration of the mucus layer and therefore may increase drug concentration at the site of action. These systems can reside in the stomach for several hours, so in this way they significantly prolong the gastric residence time of drugs resulting in improvement of the dissolution as well as bioavailability of the drugs that are poorly soluble in a high pH environment. These systems are also used for local delivery of drugs to the stomach and proximal small intestine. Gastroretention property helps to provide better availability of new products with new therapeutic possibilities and benefits for patients. Lots of attempts have been made to develop hydrodynamically balanced delivery systems. Swelling, floating, high-density, and mucoadhesive systems have been developed to increase gastric retention time of the dosage forms. Various factors such as, density of dosage form, gender, posture, age, gastric pH, size of dosage form, food intake and nature of food, motility of intestine may affect the gastric retention time of the drug delivery systems. In this review, we shall discuss about all the possible classes of drug delivery systems that are included as hydrodynamically balanced drug delivery systems.
Keywords: Hydrodynamically balanced drug delivery system, gastroretention, floating system, bioadhesive, high-density system, swelling system