Duran S H, Ravis W R, Pedersoli W M, Schumacher J
Am J Vet Res. 1987 May;48(5):807-10.
Pharmacokinetics of phenobarbital was examined in 6 mature horses after 12 mg of phenobarbital/kg of body weight was infused over 20 minutes. Biexponential decrease in serum phenobarbital concentrations was observed with a distribution-phase half-life of 0.101 +/- 0.086 hour (mean +/- SD) and a terminal-phase elimination half-life of 18.3 +/- 3.65 hours. The volume of distribution at steady state was 0.803 +/- 0.070 L/kg. Total body clearance of phenobarbital was 30.8 +/- 6.2 ml/h/kg. The high clearance in the horse seems to explain the markedly shorter half-life of phenobarbital in this species. Seemingly, 6.65 mg of phenobarbital/kg as a 20-minute infusion given every 12 hours would provide approximate peaks of 29 micrograms/ml and troughs of 15 micrograms/ml. A loading dose of 12 mg of phenobarbital/kg would be appropriate for this regimen.
对6匹成年马进行了苯巴比妥的药代动力学研究，以每千克体重12毫克的苯巴比妥在20分钟内静脉输注。血清苯巴比妥浓度呈双指数下降，分布相半衰期为0.101±0.086小时（平均值±标准差），终末相消除半衰期为18.3±3.65小时。稳态分布容积为0.803±0.070升/千克。苯巴比妥的总体清除率为30.8±6.2毫升/小时/千克。马体内的高清除率似乎解释了该物种中苯巴比妥半衰期明显较短的原因。似乎每12小时以20分钟输注6.65毫克/千克苯巴比妥可使血药浓度峰值约为29微克/毫升，谷值约为15微克/毫升。对于该给药方案，12毫克/千克的负荷剂量是合适的。
