3种左旋多巴片剂的药物动力学及生物利用度比较

Comparison of pharmacokinetics and bioavailability of three kinds of levodopa tablets in healthy volunteers

目的 :比较 3种左旋多巴片剂 (A、B和 C片 )的生物利用度和药物动力学。方法 :8名健康志愿者分别单剂量口服 2 0 0mg 3种药物 ,血药浓度由本实验室改进的高效液相色谱法测得。结果 :左旋多巴的药 -时曲线符合二室模型 ,A、B和 C片的 tmax分别为 (4 8.47± 13.86 )、(15 2 .6 5± 46 .71)和 (31.38± 7.74) min;cmax分别为 (3.17± 1.0 7)、(1.0 4± 0 .42 )和 (3.5 5± 0 .91)︼g/ml;AUC0→∞ 分别为 (4 2 4.44± 6 7.5 0 )、(2 97.36± 5 2 .18)和 (4 0 6 .0 9± 85 .0 2 ) ︼g· m l/ min。B和 C片相对于 A片的相对生物利用度分别为 (70 .17± 7.41) %和 (97.6 3± 11.94) %。结论 :B片较 A片有达峰时间长、峰浓度低的特点 ,C片与 A片相比具有吸收快、达峰时间短的特点。

AIM: To compare the pharmacokinetics and bioavailability of 3 levodopa tablets (A, B, C). METHODS: Eight healthy volunteers were given 3 preparations with a single oral dose of 200 mg in a randomized crossover study. Plasma concentrations of levodopa were measured by high performance liquid chromatography (HPLC). RESULTS: The concentration time curves of levodopa fitted to a two compartment model. The t max of the A, B and C with A were (48 47±13 86), (152 65±46 71) and (31 38±7 74) min; the c max were (3 17±1 07), (1 04±0 42) and (3 55±0 91) μg/ml; and the AUC 0→∞ were (424 44±67 50), (297 36±52 18) and (406 09±85 02) μg·ml/min, respectively. The relative bioavailabilities of B and C with A were (70 17±7 14)% and (97 63±11 94)%. CONCLUSION: These data suggest that B has characters of slow absorption and release compared with A. C was absorbed quickly than A.