Pharmacokinetic parameters and milk concentrations of ketoprofen after administration as a single intravenous bolus dose to lactating goats

Six clinically normal lactating does were administered ketoprofen (2.2 mg/kg intravenously (i. v.)). Blood and milk samples were collected prior to and for 24 h after drug administration. Drug concentrations in serum and milk were determined by high performance liquid chromatography. Pharmacokinetic parameters from each goat were combined to obtain mean estimates (mean ± SD) of half-life of elimination ( t _½β) of 0.32 ± 0.14 h, systemic clearance ( Cl ) of 0.74 ± 0.12 L/kg· h, and volume of distribution at steady state ( V _ss) of 0.23 ± 0.051 L/kg. In milk, ketoprofen was unmeasurable by the method employed (level of detection 25 ng/mL) for all samples.