Mitman Sienna L, Mzyk Danielle A, Camacho Blanca E, Council-Troche R McAlister, Davis Jennifer, Foster Derek M, Halleran Jennifer
North Carolina State University, College of Veterinary Medicine, Raleigh, North Carolina, USA.
North Carolina State University, College of Veterinary Medicine, Department of Population Health and Pathobiology, Raleigh, North Carolina, USA.
J Vet Intern Med. 2025 Jul-Aug;39(4):e70167. doi: 10.1111/jvim.70167.
Phenazopyridine is used for ancillary pain management in the treatment of goats with obstructive urolithiasis. However, there are no published studies on the pharmacokinetics, safety, or efficacy of phenazopyridine in goats.
HYPOTHESIS/OBJECTIVES: Determine the pharmacokinetic parameters of phenazopyridine after oral administration in goats with obstructive urolithiasis after tube cystostomy surgery.
Six male goats, ages 3 months to 4 years.
Prospective, observational study. Goats presenting to a veterinary institution diagnosed with obstructive urolithiasis underwent a tube cystostomy surgery. After surgery, phenazopyridine (4 mg/kg PO q12h) was administered. Plasma and urine samples were collected at predetermined intervals, and the concentration of phenazopyridine and clinically relevant metabolites was determined using ultra high-performance liquid chromatography with mass spectrometry. The pharmacokinetic parameters were determined using non-compartmental analysis.
The harmonic mean terminal elimination plasma half-life (T), geometric mean maximum plasma concentration (C), and area under the curve (AUC) were 0.5 h (0.22-1.57 h), 263.4 ng/mL (137.35-1047.88 ng/mL), and 0.69 hng/mL (0.10-2.99 hng/mL), respectively for phenazopyridine. The concentration of phenazopyridine in urine samples was below the limit of assay detection (1.5 ng/mL) in all but one sample.
Phenazopyridine was rapidly eliminated from plasma and did not concentrate at detectable levels in the urine after oral administration.
非那吡啶用于辅助治疗患有阻塞性尿路结石的山羊的疼痛。然而，关于非那吡啶在山羊体内的药代动力学、安全性或疗效尚无已发表的研究。
假设/目标：确定在膀胱造瘘管手术后患有阻塞性尿路结石的山羊口服非那吡啶后的药代动力学参数。
6只雄性山羊，年龄3个月至4岁。
前瞻性观察研究。被诊断患有阻塞性尿路结石并送至兽医机构的山羊接受了膀胱造瘘管手术。术后，给予非那吡啶（4mg/kg口服，每12小时一次）。在预定时间间隔采集血浆和尿液样本，使用超高效液相色谱-质谱法测定非那吡啶及临床相关代谢物的浓度。采用非房室分析确定药代动力学参数。
非那吡啶的谐波平均终末消除血浆半衰期（T）、几何平均最大血浆浓度（C）和曲线下面积（AUC）分别为0.5小时（0.22 - 1.57小时）、263.4ng/mL（137.35 - 1047.88ng/mL）和0.69小时ng/mL（0.10 - 2.99小时ng/mL）。除一个样本外，所有尿液样本中非那吡啶的浓度均低于检测限（1.5ng/mL）。
口服后，非那吡啶从血浆中迅速消除，且在尿液中未浓缩至可检测水平。
