Formulation and Evaluation of Floatting Drug Delivey System of Famotidine

OBJECTIVES: The concept of floating tablets can be utilized to provide a more reliable and long lasting release of drug in the stomach for local and systemic action. The floating tablets beneficially alter the absorption of a drug, thus enhancing its bioavailability. They prolong dosing intervals which will allow to develop once a day formulations and thereby increase patient compliance beyond the level of existing dosage forms by achieving control over gastric residence time. Famotidine, being a poorly bioavailable drug due to reasons unrelated to hepatic metabolism, is ideally suited to be formulated as a floating drug delivery system to improve its PK/PD profile. Hence, the objective of the present work was to design, develop, evaluate and optimize floating drug delivery system (FDDS). The purpose of this research was to prepare a floating drug delivery system of Famotidine and to compare the floating ability and sustained release effect of synthetic and natural polymers, which are designed to increase the gastric residence time, thus prolonging the drug release with localized drug action. METHOD: The floating tablets of Famotidine tablets were prepared by wet granulation method (effervescent method) by using the synthetic polymers HPMC15cps, HPMC K 100M and Carbopol 934P and the natural polymers used are chitosan and Psyllium husk. RESULTS: The compatibility study of Famotidine and other polymers implies the information that there is no interaction between drug and polymer. All the HBS formulations made by synthetic polymers showed good invitro floating properties and sustained release ability when compared to natural polymers with same concentrations of gas generating agents, sodium bicarbonate and citric acid. The formulation SPF5 showed better floating lag time and better sustained release, when compared to other synthetic and natural polymer formulation. Accelerated stability studies of the optimized formulation indicated no appreciable change in the drug content and in-vitro drug release rates of formulation. CONCLUSION: The synthetic polymers are better when compared to natural polymers (Chitosan and Psyllium husk) used in case of floating tablets. The best formulation SPF5 regression analysis of drug dissolution profiles indicated that it follows zero order drug release and Non-fickian diffusion mechanism