Design and Evaluation of Buccal Films of an Antihypertensive Drug

Olmesartan medoxomil is an angiotensin II antagonist used as an antihypertensive drug which has poor oral bioavailability. Hence, an attempt was made to prepare and evaluate mucoadhesive buccal films containing Olmesartan medoxomil as model drug. Various mucoadhesive buccal films were prepared by employing HPMC alone, and in combination with Eudragit RL100, Carbapol 934, Ethyl cellulose were prepared by solvent casting method using ethanol , water and acetone as solvents, tween 80 as solubilising agent and glycerine as plasticizer. The prepared mucoadhesive buccal films were evaluated for their physic-chemical parameters such as thickness uniformity, weight uniformity, folding endurance, drug content , surface pH, swelling index, bioadhesion, percentage moisture loss and uptake, vapor transmission rate. The formulations exhibited good results. In – vitro drug release studies were conducted for OLM loaded films in phosphate buffer (pH 6.8) solution. The drug release was in the range of 67 to 90 % in 6hrs.. Stability studies were carried out with selected formulation. In- vivo release was evaluated in rabbits by patch test and it showed good correlation with the in-vitro release data. Drug release was found to be diffusion following zero order as per kinetic studies.