Design and evaluation of buccal patches containing combination of hydrochlorothiazide and atenolol

Abstract

Objective: Buccal patch is a non-dissolving thin matrix modified release dosage form which was developed to administer into the unconscious and less co-operative patients. Methods: The mucoadhesive buccal patches of hydrochlorothiazide (HCZ) and atenolol (ATN) were prepared by solvent casting technique using various concentrations of sodium alginate, hydroxyl propyl methyl cellulose, carbopol 934P and sodium carboxy methyl cellulose polymer and polyvinyl alcohol as a backing layer. The formulated patches were evaluated for their physicochemical parameters like thickness, weight variation, surface pH, content uniformity, folding endurance, swelling percentage studies and tensile strength, in vitro and ex vivo drug permeation. Results: The infra-red (IR) spectra showed no interaction between drug and polymer. Physicochemical characteristics of all the samples were found to be satisfactory and well within the range. Swelling of the films were increased with the increasing content of the polymers and it was found that swelling front erosion was comparably slower in the formulations with the carbopol 934 and HPMC. This is probably due to their marked viscous properties and therefore formulation provided sustained release of the drug. The percentage drug content of all the formulations were found to be in the range of 97-99 %. Among the patches, FC (Carbopol 934 and HPMC) patches were considered satisfactory for maintaining the in vitro residence in the oral cavity for almost 8h. Formulations FD (with CP and NaCMC) and FC showed high tensile strength and % E/B which is an indication of the strength and elasticity of the patch. The films were exhibited sustained release for more than 6 h which was confirmed by the in vitro release data and kinetic data reveals the combination of diffusion and erosion mechanism. The best mucoadhesive performance and matrix controlled release was exhibited by the formulation FC. Conclusion: The formulation of HCZ and ATN mucoadhesive buccal patch was found to be satisfactory and reasonable.