ABSTRACT
Purpose To prepare the sustained-release tablet of tetramethylpyrazine phosphate with hydroxypropylmethylcelluose(HPMC) as matrix material. MethodsThe paddle method and the HPLC method were erspectively used determined the cumulative drug released in vitro and the serum concentration in vivo.ResultsThe cumulative drug released in the first hour was about 20%, while in 12 hours it was above 85%. Drug release behavior can be best described by Higuchi equation, and the release rate decreased as the viscosity and/or the amount of HPMC increased. Compared with the market tablet on the rabbits, the sustained release tablet had the decreased peak concentration (P < 0.05 ); the prolonged peak time and mean residence time (P< 0.05).ConclusionsThe matrix tablet was a good sustained-release dosage form and it had a good in vitro-in vivo correlation.