Formualtion and evaluation of floating drug delivery system containing clarithromycin for Helicobacter pylori

Floating matrix tablets are designed 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. With this objective, floating dosage form containing clarithromycin as drug was designed for the treatment of Helicobacter pylori. Tablets containing hydroxypropylmethylcellulose (HPMC), drug and different additives were compressed using wet granulation and D-optimal design technique. The study shows that tablet composition and mechanical strength have great influence on the floating properties and drug release. Incorporation of gas-generating agent together with polymer improved drug release, besides optimal floating (floating lag time < 30 s; total floating time > 10 h). The drug release was sufficiently sustained (more than 8 h) and anomalous diffusion as well as zero-order was confirmed. Optimization of the evaluating parameters with 'design expert' software was employed to get final optimized formulation. The optimized formulation was obtained using 62.5% clarithromycin, 4.95% HPMC K15M, 18.09% HPMC K4M, 12.96% sodium bicarbonate which gave floating lag time < 30 s with a total floating time > 10 h, in vitro release profile very near to the target in vitro release profile and follows anomalous diffusion as well as zero order pattern of release.