Escudero E, Vicente M S, Carceles C M
Department of Pharmacology, Faculty of Veterinary Medicine, University of Murcia, Campus de Espinardo, Spain.
Res Vet Sci. 1998 Jul-Aug;65(1):77-81. doi: 10.1016/s0034-5288(98)90031-5.
The pharmacokinetics of amoxicillin/clavulanic acid (4:1) combination were studied after intravenous and intramuscular administration of single doses (25 mg kg(-1) bodyweight) to 50 pigeons. The plasma concentrations-time data were analysed by compartmental pharmacokinetics and non-compartmental methods. The disposition curves for both drugs after intravenous administration were best described by a two-compartment open model. The apparent volumes of distribution of amoxicillin and clavulanic acid were 1.77 litres kg(-1) and 1.30 litres kg(-1) respectively. The body clearances of amoxicillin and clavulanic acid were not significantly different. The elimination half-lives of amoxicillin after intravenous and intramuscular administration were 1.22 (0.09) hour and 1.52 (0.09) hour respectively, and those of clavulanic acid were 1.15 (0.08) hour and 1.49 (0.08) hour. After intramuscular administration both drugs had a significantly longer half-life (P<0.05) than that after the intravenous treatment. The bioavailability after the intramuscular injection was high and similar for both drugs (75.98 per cent for amoxicillin and 74.61 per cent for clavulanic acid). The mean peak plasma concentration of clavulanic acid (0.29 hour) was reached earlier than amoxicillin (0.38 hour) and peak concentrations were proportional to the dose of both products administered (5.81 mg litre(-1) of amoxicillin and 1.89 mg litre(-1) of clavulanic acid). From a single administration it is proposed that an intramuscular dosage regimen of 105 mg kg(-1) of the combination (84 mg kg(-1) of amoxicillin and 21 mg kg(-1) of clavulanic acid) every 12 hours will achieve minimum concentrations > or =0.5 mg litre(-1) (minimum inhibitory concentration of most susceptible pathogens).
对50只鸽子单次静脉注射和肌肉注射剂量为25mg/kg体重的阿莫西林/克拉维酸（4:1）组合后的药代动力学进行了研究。采用房室药代动力学和非房室方法分析血浆浓度-时间数据。静脉注射后两种药物的处置曲线用二室开放模型描述最佳。阿莫西林和克拉维酸的表观分布容积分别为1.77升/千克和1.30升/千克。阿莫西林和克拉维酸的机体清除率无显著差异。静脉注射和肌肉注射后阿莫西林的消除半衰期分别为1.22（0.09）小时和1.52（0.09）小时，克拉维酸的消除半衰期分别为1.15（0.08）小时和1.49（0.08）小时。肌肉注射后两种药物的半衰期均显著长于静脉注射治疗后（P<0.05）。肌肉注射后的生物利用度较高，两种药物相似（阿莫西林为75.98%，克拉维酸为74.61%）。克拉维酸的平均血浆峰浓度（0.29小时）比阿莫西林（0.38小时）更早达到，且峰浓度与两种给药产品的剂量成正比（阿莫西林为5.81mg/L，克拉维酸为1.89mg/L）。建议单次给药时，每12小时肌肉注射105mg/kg体重的组合（84mg/kg体重的阿莫西林和21mg/kg体重的克拉维酸），将达到≥0.5mg/L的最低浓度（大多数敏感病原体的最低抑菌浓度）。
