Pharmacokinetics of extended‐release ivermectin microspheres after oral administration to healthy pigs. Issue 5 (18th April 2020)

• Record Type: Journal Article
• Authors: Xu, Ying; Zhang, Shen; Qiu, Yangyang; Yu, Yang; Zhang, Yunxiao; Huang, Xianhui
• Is Part Of: Journal of veterinary pharmacology and therapeutics. Volume 43:Issue 5(2020)
• Page Start: 485
• Page End: 490
• Publication Date: 2020-04-18
• Subjects: ivermectin -- microspheres -- pharmacokinetic -- pigs; Veterinary pharmacology -- Periodicals; Therapeutics -- Periodicals; 636.0895105
• DOI: 10.1111/jvp.12863
• Languages: English
• ISSNs: 0140-7783

Abstract

Abstract: We compared the pharmacokinetics of ivermectin premix and ivermectin microspheres in pigs after single and multiple administration regimes. In the single‐dose experiments, 24 piglets were randomly divided into three groups and given ivermectin at 0.3 mg/kg using (a) 1.0% ivermectin administered subcutaneously, (b) 0.25% ivermectin premix orally, and (c) 0.25% ivermectin microspheres orally. In the multiple‐dose experiment, 6 pigs in two equal groups received ivermectin premix and microspheres orally at 0.3 mg/kg for 7 consecutive days to monitor the valley plasma levels. The plasma samples were detected by fluorescence high‐performance liquid chromatography, and concentration–time data were fitted to a noncompartmental model. After oral administration of ivermectin microspheres at a single dose, the elimination rate constant (Kel), the half‐life (t1/2 ), the peak time (Tmax ), the mean residence time (MRT), and the peak concentration (Cmax ) were 0.012 ± 0.0031/hr, 59.94 ± 20.18 hr, 9.50 ± 0.93 hr, 55.96 ± 11.40 hr, and 37.75 ± 3.45 ng/ml, respectively. The Cmax of microspheres was not statistically different ( p > .05) compared with that of premix groups (39.81 ± 5.83 ng/ml). Moreover, the AUC of the microcapsule groups was increased from 1, 129.76 ± 245.62 to 1, 607.33 ± 343.35 hr ng/ml compared with the premix groups, and the relative bioavailability increased by an average of 17.53% after oral administration with ivermectin microspheres. Multiple‐dose administration also indicated pigs fed with ivermectin microspheres can get a higher minimum steady‐state concentration and a longer maintenance time than ivermectin premix.