Buccoadhesive gels of glibenclamide: a means for achieving enhanced bioavailability.

The aim of the present study was to formulate and evaluate buccoadhesive gels of model drug, glibenclamide indented as an alternate route of drug delivery to have enhanced bioavailability. The buccoadhesive gels were prepared by solution polymerization technique containing Hydroxy Propyl Methyl Cellulose (HPMC, E15 LV) and Carbopol (CP, 934P). An apparatus, simulating the in-vivo conditions of the mouth was designed in order to assess in-vitro release kinetics of the prepared gels. The gels were also evaluated for buccoadhesive strength, hydration, and swelling index, and viscosity. In-vivo evaluation for pharmacodynamic and pharmacokinetic properties of the optimized gel was done in rabbits. The drug release of buccoadhesive gels through rabbit buccal mucosa increased significantly (p < 0.05) by the use of penetration enhancers. The release kinetics followed Higuchi model with release mechanism being Fickian diffusion. In-vivo results of the optimized gel (2% CP: 2% HPMC) revealed that the gel successfully prevented severe hypoglycemia, showed sustained action, and enhanced relative bioavailability with and without penetration enhancers as compared to the marketed formulation. The buccoadhesive gels could possibly be a means for alternative dosage form in avoiding first pass metabolism and ensuring enhanced bioavailability for glibenclamide.