title: Pharmacokinetics and safety of oral administration of meloxicam to foals.
abstract: BACKGROUND
  The pharmacokinetics, efficacy, and safety of meloxicam have been evaluated in adult horses, but not foals. Physiologic differences between neonates and adults might alter drug pharmacokinetics and therapeutic index.
  
  
  OBJECTIVE
  The pharmacokinetics of meloxicam will be different in foals compared with adult horses, and foals could be at increased risk for adverse drug effects.
  
  
  METHODS
  Twenty lightbreed foals less than 6 weeks of age at commencement of the study.
  
  
  METHODS
  Single and repeated oral dose pharmacokinetics were determined for meloxicam (0.6 mg/kg) in 10 foals. The safety of the drug was further evaluated in a 2nd group of 10 foals in a randomized blinded prospective study.
  
  
  RESULTS
  Plasma concentrations after a single oral dose of meloxicam (0.6 mg/kg) and time to maximum plasma concentration were similar to adult horses. However, drug clearance was much more rapid in foals (elimination half-life 2.48 ± 0.25 hours). Administration of 0.6 mg/kg every 12 hours was well tolerated by foals for up to 3 weeks, with no evidence of drug accumulation in plasma. Adverse effects observed in adult horses at higher dose rates were not observed in foals given 1.8 mg/kg twice daily for 7 days.
  
  
  CONCLUSIONS
  Meloxicam at an oral dose rate of 0.6 mg/kg every 12 hours provided plasma concentrations likely to be therapeutic. In contrast to findings for other NSAIDs, foals appeared more resilient to the adverse effects of this drug than was observed in adult horses.
authors: School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW, Australia. sraidal@csu.edu.au
authors: S L
authors: SL
authors: Raidal
authors: S
authors: S
authors: Edwards
authors: J
authors: J
authors: Pippia
authors: R
authors: R
authors: Boston
authors: G K
authors: GK
authors: Noble
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000831:Animals, Newborn; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000009:adverse effects / Q000097:blood / Q000493:pharmacokinetics; D004311:Double-Blind Method; D005260:Female; D006207:Half-Life; D006736:Horses / Q000378:metabolism*; D008297:Male; D000077239:Meloxicam; D011446:Prospective Studies; D013843:Thiazines / Q000008:administration & dosage / Q000009:adverse effects / Q000097:blood / Q000493:pharmacokinetics*; D013844:Thiazoles / Q000008:administration & dosage / Q000009:adverse effects / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D013843:Thiazines; D013844:Thiazoles; D000077239:Meloxicam