FORMULATION AND EVALUATION OF BUCCAL PATCHES OF VENLAFAXINE

Mucoadhesive buccal patches containing venlafaxine were prepared using the solvent casting method. Chitosan and pectin were used as bioadhesive polymer and different ratios. The patches were evaluated for their physical characteristics like mass variation, drug content uniformity, folding endurance, surface pH, and in vitro drug release, in vitro buccal permeation study, ex vivo bioadhesion strength and ex vivo mucoadhesion time. Patches exhibited controlled release and released the entire contents with a period of 10 hrs. Incorporation of PVP K-30 generally enhanced the release rate. Swelling index was proportional to the concentration of chitosan. Optimized patches (F) showed satisfactory bioadhesive strength of 17.53 ± 0.47 g, and ex vivo mucoadhesion time of 10.32 hrs. The surface pH of all batches was within ± 0.4 units and thus no mucosal irritation is expected. Patches containing 1:4 of chitosan and pectin had higher bioadhesive strength with sustained drug release as compared to patches with other ratios of polymer. The optimized patch demonstrated good in vitro and ex vivo results.