Gastroretentive Drug Delivery Systems PDF

Gastroretentive Drug Delivery Systems Gastroretentive Drug Delivery Systems By Alexander Streubel, Juergen Siepmann, Roland Bodmeier Page 1  Gastroretentive Drug Delivery Systems Introduction A gastroretentive drug delivery system...

Gastroretentive Drug Delivery Systems Gastroretentive Drug Delivery Systems By Alexander Streubel, Juergen Siepmann, Roland Bodmeier Page 1  Gastroretentive Drug Delivery Systems Introduction A gastroretentive drug delivery system (GRDDS) is designed to prolong the residence time of a dosage form in the stomach. These systems are particularly useful for drugs that have an absorption window in the stomach or upper small intestine, are locally active in the stomach, or have low solubility at high pH values. Page 2  Gastroretentive Drug Delivery Systems Bioadhesive Drug Delivery Systems Bioadhesive drug delivery systems adhere to the gastric mucosa, providing prolonged retention in the stomach. Examples include formulations containing mucoadhesive polymers such as Carbopol, polycarbophil, and chitosan. These systems enhance drug absorption by increasing contact time with the gastric mucosa. Page 3  Gastroretentive Drug Delivery Systems Size-Increasing Drug Delivery Systems These systems are designed to increase in size once they reach the stomach, preventing their passage through the pylorus. This approach can involve swelling polymers or expandable structures that unfold in the stomach, like geometric shapes or gas-generating systems. Page 4  Gastroretentive Drug Delivery Systems Density-Controlled Drug Delivery Systems Density-controlled systems are designed to either float or sink in gastric fluids, thereby prolonging their retention in the stomach. High-density systems settle in the stomach, whereas floating systems remain buoyant on gastric fluids due to low density. Page 5