Comparison of pharmacokinetic profiles in hypoalbuminemia and healthy rats after parecoxib sodium injection by LC–MS/MS

Background: Valdecoxib is an active metabolite of parecoxib that has a high binding rate with plasma protein. Hypoalbuminemia may affect the pharmacokinetics process of valdecoxib. Method & results: A rapid LC-MS/MS method was applied to assay parecoxib and valdecoxib in hypoalbuminemia and healthy rats. Hypoalbuminemia rat models were established by intravenous injection of doxorubicin. The maximum plasma concentration and area under the curve values of valdecoxib in control and model groups were 744.04 ± 128.24 ng/ml, 152,727.87 ± 39,131.36 ng/ml·min and 234.25 ± 77.36 ng/ml, 29,032.42 ± 5116.62 ng/ml·min after 7.2 mg/kg parecoxib sodium injection and 371.95 ± 64.12 ng/ml, 62,218.25 ± 6876.93 ng/ml·min and 153.41 ± 33.17 ng/ml, 18,245.62 ± 868.53 ng/ml·min after 3.6 mg/kg parecoxib sodium injection, respectively. Conclusion: Hypoalbuminemia increases clearance and reduces the plasma concentration of valdecoxib in rats.