Formulation and Process Optimization of Buccoadhesive Tablet of Rabeprazole

The aim of the study was to prepare and evaluate bucco-adhesive tablets of rabeprazole sodium that avoid gastric degradation and first pass metabolism, thereby increasing the drug bioavailability and onset of action. The drug, rabeprazole sodium, belongs to a class of antisecretory compounds. In the present work, different ratios of Gantrez MS 955 along with HPMC K4M were studied to give bioadhesive strength. To stabilize the drug in human saliva different stabilizers were studied, of which sodium carbonate was found the best. A 32 full factorial design was applied to investigate the combined effect of Gantrez MS 955 concentration (X1) and HPMC K4M concentration (X2). Results of the multiple regression analysis revealed that the independent variables significantly affected the dependent variables (bioadhesive strength (Y1) and t50 (Y2)). On the basis of multiple linear regression analysis and contour plot evaluation, it was found that the effect of Gantrez is comparatively more pronounced than that of HPMC K4M on bioadhesion. The formulation F19 fulfilled all the criteria set from the desirability search. From the in vitro diffusion study flux was calculated for the optimized batch. Study of the effect of tablet diameter and the environmental factors on the bioadhesion of the tablet was done. To study the environmental factor on bioadhesion, prehydration time and contact time were considered. Result found that increase in prehydration time decrease in bioadhesive strength and increase in contact time increased bioadhesive strength. Thus a stable buccoadhesive formulation optimized for formulation ingredients and process parameters was prepared successfully.