Residue depletion study and withdrawal period for flunixin-N-methyl glucamine in bovine milk following intravenous administration.
The objective of this study was to establish a withdrawal period for flunixin in milk by quantifying 5-hydroxyflunixin, the marker residue, in bovine milk as a function of time, following intravenous treatment of lactating dairy cows with flunixin-N-methyl glucamine (Banamine or Finadyne). Lactating dairy cows were dosed on three consecutive days at 2.2 mg of flunixin free acid/kg of body weight/day. Milk was collected twice daily and assayed using a liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) procedure. The method was validated at concentrations in the range 0.5-250 ppb. The concentrations for 5-hydroxyflunixin measured 12 h after the last administration of drug ranged from 1.56 to 40.6 ppb for all cows. Milk concentrations for 5-hydroxyflunixin were used to establish withdrawal periods of 36 h using guidelines established by the U.S. Food and Drug Administration/Center for Veterinary Medicine and 24 h using guidelines established by the European Medicinal Evaluation Agency/Committee on Veterinary Medicinal Products.
Ngoh
Maureen A
MA
Drug Safety and Metabolism-Animal Health, Schering-Plough Research Institute, 144 Route 94 South, Lafayette, New Jersey 07848, USA. maureen.ngoh@spcorp.com
Wislocki
Peter G
PG
Thompson
Kenneth
K
Katz
Terry
T
Weingarten
Allan
A
TerHune
Terry
T
Hurshman
Bret
B
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D002417:Cattle / Q000378:metabolism*; D002853:Chromatography, Liquid; D003002:Clonixin / Q000008:administration & dosage* / Q000031:analogs & derivatives* / Q000493:pharmacokinetics*; D004350:Drug Residues / Q000032:analysis; D005260:Female; D007700:Kinetics; D007774:Lactation; D013058:Mass Spectrometry; D008892:Milk / Q000737:chemistry*; D013997:Time Factors
D000894:Anti-Inflammatory Agents, Non-Steroidal; C014558:flunixin meglumine; D003002:Clonixin