A novel oral controlled delivery system for benzydamine hydrochloride (BN) was developed and optimized. Hydrophilic matrix tablets of BN were prepared by using hydroxypropylmethylcellulose (HPMC) and chitosan as polymer substance to achieve required sustained release profile. The matrix tablets were prepared by both direct compression and wet granulation method. The influence of matrix forming agents and binary mixtures of them on BN release was investigated. The formulated tablets were characterized by hardness, friability, thickness, weight variation and in vitro drug release. The formulated tablets had acceptable physicochemical characters. The quantity of BN present in the tablets and the release medium were estimated by a simple, sensitive, rapid and validated HPLC method. The dissolution results show that increased amount of polymer resulted in reduced and extended drug release. F7 formulation containing 12.5% HPMC and 12.5% chitosan with direct compression method is the optimum formulation due to its better targeting profile in terms of release. Higuchi (diffusion) and Hixon-Crowell (erosion) kinetic profiles were achieved and this codependent mechanism of drug release was established. This formulation may provide an alternative for oral controlled delivery of BN and be helpful in the future treatment of primary normoreactive types of inflammation.
Keywords: Benzydamine HCl, sustained release, hydroxypropylmethyl cellulose, chitosan, dissolution