Formulation and evaluation of tramadol hydrochloride floating tablets by using different polymers

Abstract

The gastric emptying time and the variation in pH in different segments of gastrointestinal tract (GIT) are the major challenging task for the development of oral controlled release drug delivery system. Various attempts have been made to enhance the residence time of the dosage form within the stomach. Gastro retentive system can remain in the gastric region for several hours and hence significantly prolong the gastric residence time of the drug in the GIT. Potential drug candidates for gastro retentive drug delivery system (GRDDS) are drugs, which are locally active in the stomach eg. Misoprostol, antacids etc., and drugs that have narrow absorption window in GIT eg. L-DOPA, para amino, benzoic acid etc. In addition drugs which are unstable in the intestinal or colonic environment like captopril and metronidazole. It has been suggested that prolonged local availability of antimicrobial agents may augment their effectiveness in treating H. pylori related peptic ulcer. Moreover, it has been reported that bactericidal effect of clarithromycin and garcinol are time and concentration dependent. GRDDS however, are not suitable for drugs that may cause gastric lesions eg. Non-steroidal anti inflammatory drugs.