Pharmacokinetics of Single Dose and Multidose Oral Gabapentin in Goats (Capra aegagrus hircus).

Abstract

There is a shifting public perception of animal welfare that has increased demand for establishing pain management strategies in livestock. Gabapentin is often utilized in practice to mitigate neuropathic pain. However, there is little pharmacokinetic information to guide its use in goats. The objectives of this study were to describe the pharmacokinetics of oral gabapentin in goats given as a single dose (SD) and multidose (MD) regimen, as well as to document any adverse effects after administration. Six healthy adult goats were administered 15 mg/kg of gabapentin orally once for the SD trial, and every 12 h for 6 doses for the MD trial. Plasma samples were collected and analyzed via reversed-phase high-performance liquid chromatography. After SD administration, maximum plasma concentration, time to maximum concentration, and elimination half-life were: 3.22 μg/mL; 4.49 h; and 8.15 h, respectively. After MD administration, maximum plasma concentration and time to maximum concentration were: 4.56 μg/mL and 2.24 h. Accumulation ratio (R) was 1.66 ± 0.81 when comparing the MD AUC12_h to the SD AUC12_h. Clinicians should be aware of the potential for increased accumulation ratio with multiple dosing strategies.