Pharmacokinetics of a 24-hour intravenous ketoprofen infusion in children

Background: No pharmacokinetic data are available with respect to the plasma concentration of ketoprofen during intravenous infusion in children. Methods: We present here the pharmacokinetics of ketoprofen after a 10-min intravenous infusion of 1 mg/kg followed by a 24-h infusion of 4 mg/kg in 18 children aged 7 months to 16 years. Venous blood samples were collected at 5 min, 1, 2, 4, 24 following the loading dose, and then 1, 2 and 4h after the end of the infusion. A validated HPLC method was used to measure plasma levels of ketoprofen. Results: The steady state plasma concentration of ketoprofen was 2.0 mug/mL (range 1.3-2.7 mug/mL). The clearance of ketoprofen was 0.09L.h(-1).kg(-1) (range 0.06-0.13L-h(-1).kg(-1)). The distribution volume was 0.16L/kg (range 0.12-0.21L/kg). The terminal half-life was 1.3h (range 0.8-1.7h). Conclusion: The pharmacokinetics of ketopofen in children is similar to that reported in adults. Our results indicate that ketoprofen is a feasible drug for continuous intravenous infusion in acute pain treatment in children.