Development and Characterization of Novel Trans Buccoadhesive Bilayer Tablets of Tapentadol Hydrochloride

Buccoadhesive bilayer tablets of Tapentadol Hydrochloride were prepared and evaluated in this investigation. Tapentadol is a centrally-acting opioid analgesic, having potency between morphine and tramadol. The direct compression method was used for preparing tablets. The polymers were employed in the formulations are Carbopol 934 P, Eudragit RL 100, sodium alginate, Chitosan, and polyvinylpyrrolidone-K30 (PVP) and ethyl cellulose (EC) as a backing layer. The prepared formulations were evaluated for their physicochemical characteristics, swelling index, surface pH, ex vivo buccoadhesive strength, in vitro, in vivo drug release and ex vivo permeation studies. The significant differences in the results were observed, which dependent on characteristics and composition of bioadhesive materials used. Stability studies were conducted in natural human saliva and accelerated conditions, results reveals no significant change in physical appearance. Drug content, buccoadhesive strength and the P-value shown statistically significant at <0.05. Ex vivo mucous irritation by histological examination reveals, the administration site of buccal tablet over the buccal mucosa did not cause any irritation, ulceration, inflammation and redness, and it resembles to controlled buccal mucosa. Good correlations were observed between in vitro and in vivo drug release, with a correlation coefficient of 0.997. Drug diffusion from buccal tablets showed apparently zero order kinetics and release mechanism was diffusion controlled after considerable swelling.