GRDDS(gastro retentive drug delivery systems) a novel approch for drug delivery.. sagar bansal m.pharma.

5. Absorption window

12. Drugs that are unsuitable for gastro-retentive drug delivery system: a . Enteric coated systems. b. Drugs intended for selective release in the colon e.g. 5-aminosalicylic acid and corticosteroids. c. Drugs that have very limited acid solubility e.g. phenytoin. d. Drugs that suffer instability in the gastric environment e.g. erythromycin

16. Schematic localization of an intragastric floating system and a high-density system in the stomach.

18. Hydrodynamically balanced systems: HBS™ Schematic diagram shows the mode of action for HBS TM (Bogentoft, 1982).

24. Different geometric forms of unfoldable systems proposed by Caldwell et al. From Caldwell et al. (1988). Expandable systems

26. On the left, superporous hydrogel in its dry (a) and water-swollen (b) state. On the right, schematic illustration of the transit of superporous hydrogel. From Gutierrez-Rocca, (2003). Superporous hydrogels