Quantification of levetiracetam in plasma and urine and its application to a pharmacokinetic study of traumatic brain injury patients.

Background: Levetiracetam is an antiepileptic drug used to prevent or treat seizure in patients with severe traumatic brain injury. This study aimed to develop and validate methodology suitable for measuring levetiracetam concentrations in human plasma and urine. Methods: Plasma or urine (10 μl) samples were spiked with [ 2 H 6 ]-levetiracetam and processed using an acetonitrile precipitation. ESI-LC-MS/MS was employed for analyte detection. Results: The levetiracetam calibration was linear from 0.1 to 50 mg/l in a combined matrix of plasma and urine. Intra- and inter-assay imprecision and accuracy in plasma were <7.7 and 109%, and in urine were <7.9 and 108%, respectively. Conclusion: The validated method was applied to a pharmacokinetic study of levetiracetam in critically ill patients with severe traumatic brain injury.