Pharmacokinetics of ivermectin in llamas (Lama glama).
The pharmacokinetic behaviour of ivermectin was investigated in adult llamas (Lama glama) by using high performance liquid chromatography with a lower limit of quantification of 2 ng/ml to measure its concentration in serum. Llamas were treated with one of three commercial formulations (injectable, pour-on or oral paste) at dosages recommended by the manufacturer, or with an experimental injectable sustained-release formulation. In five llamas given 1 per cent ivermectin subcutaneously at 200 microg/kg, the median peak serum concentration (Cmax) was 3 ng/ml and the area under the serum concentration-time curve (AUC) was 13.5 ng x day/ml. In six llamas treated topically with 0.5 per cent ivermedin pour-on at 500 microg/kg, Cmax was 2.5 ng/ml or less and the AUC was 7.75 ng x day/ml or less. In seven llamas with measurable concentrations of ivermedin, the median times to peak serum concentration (tmax) were six days after subcutaneous injection and seven days after treatment with the pour-on formulation. In six llamas, the serum concentration of ivermectin remained less than 2 ng/ml for 124 hours after treatment with a 1.87 per cent oral paste at 200 microg/kg. In five llamas treated subcutaneously with 25 per cent ivermectin sustained-release microspheres at 1500 microg/kg, the median Cmax was 5 ng/ml and the median AUC was 224 ng x day/ml.
Jarvinen
J A
JA
Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames 50011, USA.
Miller
J A
JA
Oehler
D D
DD
D000818:Animals; D000871:Anthelmintics / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D002161:Camelids, New World; D002851:Chromatography, High Pressure Liquid; D003692:Delayed-Action Preparations; D005260:Female; D007279:Injections, Subcutaneous; D007559:Ivermectin / Q000097:blood / Q000493:pharmacokinetics*; D008297:Male
D000871:Anthelmintics; D003692:Delayed-Action Preparations; D007559:Ivermectin