Design and Characterisation of Mucoadhesive Buccal Patch of Glimepride

The buccal region offers an attractive route of administration for systemic drug delivery. Glimepiride is a potent drug against Diabetes mellitus-II with a half life of 3-5 hours. Though Glimepride has 100% oral absorption, due to high first pass metabolism its bioavailability is less. The recommended dosage is 4 mg b.i.d leading to admistration of the drug twice a day. The present study is aimed to design sustained release mucoadhesive buccal patch formulation of Glimepride in order to by-pass GIT and release the drug for extended periods of time. Buccal patches were formulated using polymers Carbopol 934 P(CP 934 P), Ethyl Cellulose (EC) and Hydroxy Propyl Methyl Cellulose(HPMC) in various proportions and combinations. Tween 80 was used as permeation enhancer and glycerine as plasticizer. The patches were prepared by solvent casting method. The designed patches were evaluated for thickness uniformity, folding endurance, weight uniformity, content uniformity and swelling behaviour. In vitro diffusion studies were conducted for 24 hours in phosphate buffer (pH 6.6) solution using dialysis membrane. Formulation containing maximum amount of swellable and hydrophilic polymer HPMC K100M and CP 934 P, showed higher swelling index and could sustain for 24 hours. This occurred due to more hydrophilic polymeric matrix composition which retarded the release of the drug. The diffusion followed zero order kinetic model.( R2 = 0.9778)