Hydrodynamically Balanced Systems using Famotidine: Influence of natural and synthetic polymers

Abstract

This study focuses on the development and evaluation of floating sustained-release tablets of Famotidine using the Hydrodynamically Balanced System (HBS) approach to prolong gastric retention and enhance bioavailability for the management of peptic and duodenal ulcers. Floating tablets were formulated via wet granulation employing both synthetic (HPMC 15cps, HPMC 100M, Carbopol) and natural polymers (Chitosan, Psyllium husk), along with gas-generating agents to achieve buoyancy. All prepared formulations were assessed for drug-polymer compatibility, pre-compression parameters, and post-compression characteristics, including in-vitro buoyancy and drug release. Infrared spectroscopy confirmed the compatibility between Famotidine and the polymers. The synthetic polymer-based formulations demonstrated superior performance compared to those with natural polymers. Among all, formulation SPF5, containing HPMC 15cps, was identified as the optimized batch. It exhibited an excellent floating lag time of 15 seconds, a total floating time of over 23 hours, a high swelling index (68.38%), and sustained drug release over 12 hours in simulated gastric fluid. The drug release from SPF5 followed zero-order kinetics (R²=0.964) and the Higuchi model, indicating a diffusion-based, Non-Fickian release mechanism. Stability studies confirmed the formulation's robustness over time. In conclusion, the successful development of Famotidine HBS tablets presents a promising strategy for controlled drug delivery, offering improved therapeutic efficacy over conventional dosage forms.