To investigate the effect of pretreatment with rifampicin (rifampin) on the pharmacokinetics of tinidazole in healthy male volunteers. Before/after non-blinded investigation conducted in healthy volunteers. 12 healthy male volunteers with a mean age of 24 ± 3 years. After an overnight fast, tinidazole (500mg tablet) was administered to the volunteers, either alone or after a 5-day pretreatment period with a once-daily dose of rifampicin 600mg (2 × 300mg capsules) under direct observation. Serum concentrations of tinidazole were measured by reverse-phase high performance liquid chromatography Pharmacokinetic parameters were determined from noncompartmental model analysis using the computer program RAMKIN. A significant difference was observed in area under the concentration-time curve (AUC) from 0 to 48 hours (254.77 ± 31.46 vs 208.07 ± 25.57 mg/h/L, p < 0.0001), AUC from 0 to infinity (299.86 ± 47.70 vs 231.54 ± 36.19 mg/h/L, p < 0.0001], elimination half-life (16.98 ± 2.73 vs 13.93 ± 3.45h, p < 0.0018) and clearance (27.62 ± 3.61 vs 35.82 ± 4.95 ml/h/kg, p < 0.0001) of tinidazole administered before and after rifampicin pretreatment. However, peak concentration (Cmax), time to reach Cmax and apparent volume of distribution were not affected significantly. Rifampicin pretreatment reduced the AUC of tinidazole by 23% and increased the clearance by 29%. This may be due to increased metabolism of tinidazole as a result of the induction of cytochrome P450 2C9 and 3A4 in liver/intestine and/or P-glycoprotein-mediated exsorption into the intestines. This interaction, however, may not have significant clinical relevance and does not warrant dosage adjustment because the extent of alteration in bioavailability of tinidazole is less than 25%.
研究
利福平(rif
AMpicin)预处理对健康男性志愿者体内
替硝唑药代动力学的影响。在健康志愿者中进行前/后非盲法研究。12 名健康男性志愿者,平均年龄为 24 ± 3 岁。在一夜禁食后,在直接观察下给志愿者单独服用
替硝唑(500 毫克片剂)或在 5 天预处理期后服用
利福平 600 毫克(2 × 300 毫克胶囊)。通过反相高效
液相色谱法测定血清中
替硝唑的浓度,并使用计算机程序 R
AMKIN 通过非室模型分析确定药代动力学参数。从 0 到 48 小时的浓度-时间曲线下面积(AUC)(254.77 ± 31.46 vs 208.07 ± 25.57 mg/h/L,p < 0.0001)、从 0 到无穷大的浓度-时间曲线下面积(AUC)(299.86 ± 47.70 vs 231.54 ± 36.19 mg/h/L,p <;0.0001],消除半衰期(16.98 ± 2.73 vs 13.93 ± 3.45h,p <;0.0018)和清除率(27.62 ± 3.61 vs 35.82 ± 4.95 ml/h/kg,p <;0.0001)。然而,峰浓度(Cmax)、达到 Cmax 的时间和表观分布容积没有受到明显影响。
利福平治疗后,
替硝唑的 AUC 降低了 23%,清除率增加了 29%。这可能是由于肝脏/肠道中细胞色素 P450 2C9 和 3A4 的诱导作用和/或 P 糖蛋白介导的肠道吸收作用导致
替硝唑的代谢增加。不过,这种相互作用可能不会对临床产生重大影响,也不需要调整剂量,因为
替硝唑生物利用度的改变程度低于 25%。