目的 制备右佐匹克隆定时释放片，并考察其体外释药特性。方法 分别以HPMC作为溶胀层包衣材料，以乙基纤维素水分散体作为控释层包衣材料，采用高效包衣机制备右佐匹克隆定时释放片，考察影响释放度的主要因素，并测定体外释放度以考察体外释药行为。结果 确定了影响右佐匹克隆释放的处方因素，体外释放度研究结果表明，该制剂可达到脉冲式释放。结论 右佐匹克隆定时释放片可以达成两次定时脉冲释放，符合让失眠患者快速入睡并维持6 h以上睡眠状态的设计初衷。

Objective To prepare Eszopiclone Time-controlled Release Tablets and investigate the release characteristics in vitro. Methods Eszopiclone Time-controlled Release Tablets were prepared by using high efficient coating machine. HPMC was used as swelling material, and EC aqueous dispersion as controlled-release coating material. The main factors which influence the drug release characteristics were evaluated, and the dissolution data in vitro were investigated. Results The main factors affecting drug release were identified. The dissolution data in vitro showed that Eszopiclone Time-controlled Release Tablets could achieve the expected pulse release. Conclusion Eszopiclone Time-controlled Release Tablets can achieve twice pulse release, meets the original requirement of helping patients with insomnia to fall asleep quickly and a sleep duration of more than 6 hours.