Pharmacokinetics of tolfenamic acid in goats after different administration routes

Abstract

The aim of this study was to determine the pharmacokinetics and bioavailability of tolfenamic acid in goats after intravenous (IV), intramuscular (IM), subcutaneous (SC), and oral (PO) administrations at 2 mg/kg dose. In this study, eight clinically healthy goats were used. The study comprised four periods, according to a crossover design with at least a 15‐day washout period between treatments. Plasma concentrations of tolfenamic acid were determined by HPLC‐UV, and the pharmacokinetic parameters were estimated using a non‐compartmental method. Following IV administration, terminal elimination half‐life, volume of distribution at steady state, and total clearance were 1.60 h, 0.37 L/kg, and 0.27 L/h/kg, respectively. The mean peak plasma concentration following IM, SC, and PO administrations was 1.77, 1.22, and 0.30 μg/ml, respectively. The mean bioavailability following IM, SC, and PO administrations was 64.46, 55.43, and 19.46%, respectively. The PO route, which exhibits both the low plasma concentration and bioavailability, is not recommended in goats. The IV, IM, and SC routes, which show comparable pharmacokinetic profiles, may be proposed for use in goats. However, the multi‐dose and pharmacodynamic studies are necessary to establish more accurately its safety and efficacy in the goat.

Pharmacokinetics and bioavailability of carprofen in sheep

“…The elimination t 1/2ʎz of carprofen was 43.36 h, which was similar to the previously reported in calves (43.4 h, Delatour et al, 1996), and longer than that reported for sheep, dog, horse, cat, and cow (8.00–33.7 h, Lohuis et al, 1991; McKellar et al, 1990, 1991; Parton et al, 2000; Welsh et al, 1992). Carprofen has longer elimination t 1/2ʎz than other NSAIDs including tolfenamic acid, meloxicam, ketoprofen, and flunixin meglumine used in veterinary medicine (Corum et al, 2018; CVMP, 1995; Tekeli et al, 2020; Turk et al, 2021b; Welsh et al, 1993). The reason for the difference in the elimination t 1/2ʎz of carprofen in sheep may be due to the difference in breed (Akkaraman vs. Suffolk), weight (42.63 ± 3.38 vs. from 53 to 66 kg), and the sensitivity of analytical method (0.02 μg/ml vs. 0.1 μg/ml).…”

Robenacoxib pharmacokinetics in sheep following oral, subcutaneous, and intravenous administration

“…The difficulty in administering injectable drugs in some cases, alongside cost and time, are other reasons on the list too (Huxley & Whay, 2007 ; Lizarraga & Chambers, 2012 ). It should be noted that a few NSAIDs for sheep and goats are approved in some nations, such as Canada, New Zealand, Australia, India, Mexico, Peru, and Costa Rica (Anonymous, 2016 ; 2020 ; Turk et al, 2021 ).…”

Preparation, Characterization and Pharmacokinetics of Tolfenamic Acid-Loaded Solid Lipid Nanoparticles

“…The main mechanism of action of TA is the prevention of COX enzyme formation by prostaglandins through the inhibition of prostaglandin production throughout the body, which reduces inflammation, pain, and fever [10,11]. TA is rapidly absorbed and eliminated by the body with a short half-life (1.94-5.71 h) [12,13]. Currently, there are only two common dosage forms of TA available on the market, i.e., tablets and injections.…”