Study on Preparation and Pharmacokinetics of Tramadol Hydrochloride Microspheres Sustained Release Tablets

OBJECTIVE To study the method that how to prepare tramadol hydrochloride microspheres sustained release tablets, and pharmacokinetics and relative bioavailability of microspheres sustained release tablets in dogs. METHODS EC was selected as the preparation of material. Tramadol hydrochloride microspheres sustained release tablets were prepared by the spray drying method, direct tabletting. The microspheres sustained release tablets and commercial tablets in dogs were performed in single dose experiments by HPLC. RESULTS The pharmacokinetic parameters for the single dose of the microspheres sustained release tablets and commercial tablets were as follows: C_max (322±16)ng·mL^-1 and (346±11)ng·mL^-1; T_max (2.5±0.3)h and (1.5±0.4)h; t_1/2 (4.31±0.84)h and (4.95±0.79)h, AUC_0→t (2 940.8±32.1)ng·h·mL^-1 and (3 560.9±18.6)ng·h·mL^-1, the relative bioavailability was 121.09%. CONCLUSION Tramadol hydrochloride microspheres sustained release tablets has a sustained- release effect.