Toutain P L, Upson D W, Terhune T N, McKenzie M E
Ecole Nationale Vétérinaire de Toulouse, Unité associée INRA de Physiopathologie et Toxicologie Expérimentales, Toulouse, France.
Vet Parasitol. 1997 Sep;72(1):3-8. doi: 10.1016/s0304-4017(97)00070-8.
Plasma pharmacokinetics were compared for 40 cattle dosed by subcutaneous injection with doramectin or ivermectin (200 micrograms kg-1), commercial formulations of doramectin or ivermectin, 20 cattle per product). Doramectin exhibited a similar peak plasma concentration to ivermectin (about 32 ng ml-1), but the time to Cmax was longer for doramectin (5.3 +/- 0.35 days) than for ivermectin (4.0 +/- 0.28 days). The area under the curve from time 0 to infinity post-injection was significantly higher (p < 0.001) for doramectin (511 +/- 16 ng day ml-1) than for ivermectin (361 +/- 17 ng day ml-1). This was explained by a lower clearance, a lower volume of distribution and, probably, a higher bioavailability of doramectin over ivermectin. It is concluded that the pharmacokinetic differences between doramectin and ivermectin may explain the longer duration of preventive efficacy of doramectin.
对40头牛进行皮下注射多拉菌素或伊维菌素（200微克/千克）（每种产品20头牛），比较了多拉菌素和伊维菌素（多拉菌素和伊维菌素的商业制剂）的血浆药代动力学。多拉菌素的血浆峰值浓度与伊维菌素相似（约32纳克/毫升），但多拉菌素达到最大血药浓度的时间（5.3±0.35天）比伊维菌素（4.0±0.28天）长。注射后从时间0到无穷大的曲线下面积，多拉菌素（511±16纳克·天/毫升）显著高于伊维菌素（361±17纳克·天/毫升）（p<0.001）。这可以用多拉菌素比伊维菌素清除率更低、分布容积更小以及可能生物利用度更高来解释。得出结论，多拉菌素和伊维菌素之间的药代动力学差异可能解释了多拉菌素预防效果持续时间更长的原因。
