Abstract

Background: Floating tablets extend drug residence time, enhance bioavailability and promote the delivery of local drugs to the stomach. With this objective, floating tablets were prepared for the treatment of gastric ulcers containing aqueous extract of liquorice and Isabgol.

Methods: Tablets containing HPMC K100M (hydrophilic polymer), liquorice extract, sodium bicarbonate (gas generating agent), talc, and magnesium stearate were prepared using direct compression method. Physical parameters of formulations such as diameter, thickness, hardness, friability, weight uniformity, drug content, buoyancy time, dissolution, and the mechanism for drug release, were assessed. The formulations have been optimized based on buoyancy time and in- vitro drug release.

Results: The diameter of all formulations was in the range 11.310-11.833 mm; thickness was in the range 4.02-4.071 mm. The hardness ranged from 3.1 to 3.4 kg/cm. All the formulations passed the USP requirements for friability and uniformity of weight. All tablet formulations had a buoyancy period of less than 5 min and throughout the research, the tablet stayed in floating condition. All tablet formulations were accompanied in drug discharge by zero-order kinetics and Korsmeyer-Peppas model.

Conclusion: It was discovered that the optimized formulation was F7, which released 98.5 percent of the drug in 8 hr. in-vitro, while the buoyancy time was 3.5 min. For gastroretentive drug delivery systems, formulations containing Isabgol, sodium bicarbonate and HPMC K100 M in combination may be promising.