Volume 6

April-June 2014

Optimization of hydrodynamically balanced tablets of clarithromycin: An approach to prolong and increase the local action by gastric retention

Saripilli Rajeswari, Sravya Kudamala, Kolapalli Venkata Ramana Murthy

Abstract:
The objective of the present investigation is to formulate gastro retentive floating tablets (GRFT) of clarithromycin for the treatment of Helicobacter pylori, to prolong the gastric residence time after oral administration, at a particular site. Controlled release of drug is especially useful for achieving controlled plasma level as well as for improving bioavailability. The effect of formulation variables on floating lag time, t50 and t90 are also studied. The GRFT contains hydroxypropyl methylcellulose (HPMC) and hydroxyl ethyl cellulose (HEC) as release retarding polymers. The concentration of sodium bicarbonate (NaHCO3) was initially optimized. The tablets were prepared by wet granulation method and 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 the polymer concentration, 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 was observed.

Keywords: Clarithromycin, Gastro Retentive, Hydroxylethyl Cellulose, Hydroxypropyl Methylcellulose, Microcrystalline Cellulose, Sodium Bicarbonate.