Résumé
Objective: To investigate the preparation of pulsatile release tablets, the release of the drug in vitro and the pharmacokinetics in vivo . Methods: Dil tiazem hydrochloride（DIL） was used as model drug. The pulsatile release tabl e ts were prepared by dry-coated method with carnauba wax, bee wax and hydrophil i c cellulose as coating materials. The effects of formulation and technology on t he release characteri stic of diltiazem hydrochloride was investigated. The mechanism of pulsatile rel ease of the drug was proved by erosion test. The pharmacokinetic study on four h uman subjects was done by means of HPLC measurement. Results: In vitro ， delayed-release ti me t 10 was 2.1 h, the maximum release time t rm 4.0 h and t he pulsed-releas e time t 10-90 1.7 h. In vivo ， delayed-release time t la g was 5.7 h, the p eak time 8.5 h and the pulsed-release time 2.6 h. Conclusion: The rele ase of drug from pulsatile-released tablets of diltiazem hydrochloride was in a pulsed way both in vitro and in vivo .