Buccal Patches-A Review

Buccal delivery refers to the drug release which can occur when a dosage form is placed in the outer vestibule between the buccal mucosa and gingival. This route has various advantages includes bypass of first pass metabolism, better enzymatic flora for absorption and patient compliance. Buccal drug absorption occurs by passive diffusion of the nonionized species. Mucoadhesion may be affected by a number of factors, including hydrophilicity, molecular weight, cross-linking, swelling, pH, and the concentration of the active polymer. There are two types of buccal dosage form,they are matrix type and reservoir type. The basic components of buccal drug delivery system are drug substance, bio adhesive polymers, backing membrane permeation enhancers. There are two methods for preparation of buccal patches include solvent castng method and direct milling method. The evaluation tests include surface PH, thickness measurement, swelling study, thermal Analysis study, morphological characterizayion, water absorption capacity test, Ex-vivo bioadhesion test, in vitro drug release, permeation study, Ex-vivo mucoadhesion time and stability study in human saliva.