title: Pharmacokinetics of ponazuril after oral administration to healthy llamas (Lama glama).
abstract: OBJECTIVE
  To determine the pharmacokinetics after oral administration of a single dose of ponazuril to healthy llamas.
  
  
  METHODS
  6 healthy adult llamas.
  
  
  METHODS
  Ponazuril (20 mg/kg) was administered once orally to 6 llamas (day 0). Blood samples were obtained on days 0, 0.5, 1, 2, 3, 4, 5, 6, 7, 9, 11, 14, 21, 28, 35, 42, and 49. Serum ponazuril concentrations were determined by use of a validated reverse-phase high-performance liquid chromatography assay with UV absorbance detection. Pharmacokinetic parameters were derived by use of a standard noncompartmental pharmacokinetic analysis.
  
  
  RESULTS
  Mean ± SD area under the serum concentration-time curve was 7,516 ± 2,750 h•mg/L, maximum serum ponazuril concentration was 23.6 ± 6.0 mg/L, and the elimination half-life was 135.5 ± 16.7 hours. Serum concentration of ponazuril peaked at 84 hours (range, 48 to 120 hours) after administration and gradually decreased but remained detectable for up to 35 days after administration. No adverse effects were observed during the study period.
  
  
  CONCLUSIONS
  The rate and extent of absorption following oral administration of a single dose of ponazuril were sufficient to result in potentially effective concentrations, and the drug was tolerated well by llamas. At this dose, ponazuril resulted in serum concentrations that were high enough to be effective against various Apicomplexans on the basis of data for other species. The effective ponazuril concentration that will induce 50% inhibition of parasite growth for Eimeria macusaniensis in camelids is currently unknown.
authors.affiliation: Department of Animal Science, Institute of Agriculture, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996, USA. meprado@utk.edu
authors.forename: Maria E
authors.initials: ME
authors.lastname: Prado
authors.forename: Josiah T
authors.initials: JT
authors.lastname: Ryman
authors.forename: Melanie J
authors.initials: MJ
authors.lastname: Boileau
authors.forename: Tomas
authors.initials: T
authors.lastname: Martin-Jimenez
authors.forename: Bernd
authors.initials: B
authors.lastname: Meibohm
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000981:Antiprotozoal Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D002161:Camelids, New World / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000662:veterinary; D006207:Half-Life; D013997:Time Factors; D014227:Triazines / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D000981:Antiprotozoal Agents; D014227:Triazines; C415002:ponazuril