目的:研究甲地孕酮胶囊剂的药物动力学和生物利用度.方法:10名健康志愿者,随机交叉po单剂量(160 mg)甲地孕酮胶囊或片剂,采用HPLC法测定血浆中甲地孕酮浓度,估算出药物动力学参数,以甲地孕酮片剂为标准,对胶囊剂的生物利用度和生物等效性进行评价.结果:胶囊剂和片剂分别在(3.50±0.71)和(4.4O±0.84)h达到峰值(117.1±49.5)和(125.6±39.7)ng/ml;两种制剂的消除相半衰期分别为(32.5±4.97)和(32.3±4.74)h;AUC分别为(2829.3±513. 6)和(2784.2±618.9)ng·h/ml.药-时曲线符合一级吸收的二室模型.以参比制剂甲地孕酮片为标准,算得甲地孕酮胶囊的相对生物利用度为(102.6±7.71)%.结论:两种制剂具有生物等效性. Objective: To study the pharmacokinetics and bioavailability of megestrol capsules.METHODS: Ten healthy volunteers were randomized to receive a single dose (160 mg) of megestrol capsules or tablets, and the plasma concentrations of The pharmacokinetic parameters of megestrol were estimated, and the bioavailability and bioequivalence of the capsules were evaluated with megesterone tablets as standard.Results: Capsules and tablets were stable at (3.50 ± 0.71 and (4.4 ± 0.84) h, respectively. The elimination half-lives of the two preparations were (32.5 ± 4.97) and (32.3 ± 4.74) h, respectively; (2829.3 ± 513.6) and (2784.2 ± 618.9) ng · h / ml, respectively.The drug-time curve was in accordance with the first-order absorption model of two-compartment model.The reference preparation of megesterone tablets as the standard, The relative bioavailability of ketoconazole capsules was (102.6 ± 7.71)%. Conclusion: The two formulations are bioequivalent.