Formulation and Evaluation of Mouth Dissolving Tablets of Tramadol Hydrochloride

Purpose: To prepare, and evaluate in vitro and in vivo tramadol hydrochloride mouth dissolving tablets (MDT).Methods: Tramadol HCl MDT were prepared by direct compression using Pharmaburst as coprocessed excipient and compared with a reference product (Rybix ODT, 50 mg). Physicochemical parameters including hardness, friability, weight variation, disintegration time and dissolution studies were determined for all the formulations. In-vivo studies were performed for the optimized formulation (F13), using as reference, a commercial product (Trambax IR, 50 mg), by a two-way crossover design under fasting conditions on eight healthy adult human subjects. Drug-plasma concentrations obtained from the bioequivalence study for test and reference products were analyzed in each subject by high performance liquid chromatography (HPLC), and basic pharmacokinetic parameters, including Cmax, Tmax, AUC0-t, AUC0-∞, t½ and λz, were calculated.Results: The tablet formulation prepared with Pharmaburst (F13) showed good flow properties, low disintegration time (15 s) and improved drug release (99 % at 30 min) compared with those of the reference product (88 % at 30 min) and passed 6 months accelerated stability test. Bioequivalence of the test product with that of the reference product under fasting conditions was established by computing 90 % confidence interval for the In-transformed pharmacokinetic parameters of Cmax, AUC0-t and AUC0-∞ for tramadol. The 90 % confidence intervals for Cmax were 99.70 - 114.31, for AUC0-t 97.31 - 108.87 and for AUC0-∞ 97.17 - 109.75. This confidence interval, in each case, was within bioequivalence criteria limitConclusion: A suitable preparation of tramadol HCl MDT that is bioequivalent with a reference commercial product under fasting condition can be obtained when Pharmaburst is used as a disintegrant.Keywords: Bioequivalence, dissolution, Mouth dissolving tablets, Pharmaburst, Tramadol hydrochloride, Disintegration tim