Formulation and Evaluation of Gastroretentive Floating Dosage Forms of Clarithromycin

The objective of the present investigation is to formulate gastro retentive floating drug delivery systems (GRFDDS) of clarithromycin for the treatment of Helicobacter pylori, to prolong the gastric residence time after oral administration, at a particular site and controlling the release of drug especially useful for achieving controlled plasma level as well as improving bioavailability and to study the effect of formulation variables on floating lag time, t₅₀ (time required to release 50% of the drug) and t90 (time required to release 90% of the drug). The GRFDDS contains hydroxypropyl methylcellulose (HPMC) and hydroxyl propyl cellulose (HPC) as a release retarding polymer. The concentration of sodium bicarbonate (NaHCo₃) was optimized. The tablets were prepared by wet granulation method. The prepared tablets were evaluated for all their physicochemical properties, in vitro buoyancy, drug release and rate order kinetics. From the results, FHM4 was selected as an optimized formulation based on their 12 hrs drug release, minimal floating lag time and maximum total floating time. The optimized formulation followed first order rate kinetics with erosion mechanism. The optimized formulation was characterized with FTIR studies and no interaction between the drug and the polymers were observed.