Lee D D, Papich M G, Hardie E M
Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.
Am J Vet Res. 2000 Jun;61(6):672-7. doi: 10.2460/ajvr.2000.61.672.
To compare pharmacokinetic and pharmacodynamic characteristics of fentanyl citrate after IV or transdermal administration in cats.
6 healthy adult cats with a mean weight of 3.78 kg.
Each cat was given fentanyl IV (25 mg/cat; mean +/- SD dosage, 7.19 +/- 1.17 mg/kg of body weight) and via a transdermal patch (25 microg of fentanyl/h). Plasma concentrations of fentanyl were measured by use of radioimmunoassay. Pharmacokinetic analyses of plasma drug concentrations were conducted, using an automated curve-stripping process followed by nonlinear, least-squares regression. Transdermal delivery of drug was calculated by use of IV pharmacokinetic data.
Plasma concentrations of fentanyl given IV decreased rapidly (mean elimination half-life, 2.35 +/- 0.57 hours). Mean +/- SEM calculated rate of transdermal delivery of fentanyl was 8.48 +/- 1.7 mg/h (< 36% of the theoretical 25 mg/h). Median steady-state concentration of fentanyl 12 to 100 hours after application of the transdermal patch was 1.58 ng/ml. Plasma concentrations of fentanyl < 1.0 ng/ml were detected in 4 of 6 cats 12 hours after patch application, 5 of 6 cats 18 and 24 hours after application, and 6 of 6 cats 36 hours after application.
In cats, transdermal administration provides sustained plasma concentrations of fentanyl citrate throughout a 5-day period. Variation of plasma drug concentrations with transdermal absorption for each cat was pronounced. Transdermal administration of fentanyl has potential for use in cats for long-term control of pain after surgery or chronic pain associated with cancer.
比较枸橼酸芬太尼静脉注射或经皮给药在猫体内的药代动力学和药效学特征。
6只健康成年猫，平均体重3.78千克。
每只猫静脉注射芬太尼（25毫克/只；平均±标准差剂量，7.19±1.17毫克/千克体重）并通过透皮贴剂给药（25微克芬太尼/小时）。使用放射免疫分析法测量芬太尼的血浆浓度。采用自动曲线剥离法，随后进行非线性最小二乘回归，对血浆药物浓度进行药代动力学分析。利用静脉给药的药代动力学数据计算药物的经皮递送量。
静脉注射芬太尼后血浆浓度迅速下降（平均消除半衰期，2.35±0.57小时）。芬太尼经皮递送的平均±标准误计算速率为8.48±1.7毫克/小时（<理论值25毫克/小时的36%）。应用透皮贴剂后12至100小时，芬太尼的中位稳态浓度为1.58纳克/毫升。贴剂应用后12小时，6只猫中有4只检测到芬太尼血浆浓度<1.0纳克/毫升，应用后18和24小时，6只猫中有5只检测到，应用后36小时，6只猫均检测到。
在猫中，经皮给药在5天内可提供持续的枸橼酸芬太尼血浆浓度。每只猫经皮吸收的血浆药物浓度变化明显。芬太尼经皮给药有潜力用于猫术后长期疼痛控制或与癌症相关的慢性疼痛。
