1. Drug monitoring: simultaneous analysis of lamotrigine, oxcarbazepine, 10-hydroxycarbazepine, and zonisamide by HPLC-UV and a rapid GC method using a nitrogen-phosphorus detector for levetiracetam.
- Author
-
Greiner-Sosanko E, Giannoutsos S, Lower DR, Virji MA, and Krasowski MD
- Subjects
- Carbamazepine analysis, Carbamazepine blood, Humans, Lamotrigine, Levetiracetam, Nitrogen analysis, Oxcarbazepine, Phosphorus analysis, Piracetam blood, Reproducibility of Results, Ultraviolet Rays, Zonisamide, Anticonvulsants blood, Carbamazepine analogs & derivatives, Chromatography, Gas methods, Chromatography, High Pressure Liquid methods, Isoxazoles blood, Piracetam analogs & derivatives, Triazines blood
- Abstract
A high-performance liquid chromatography (HPLC) assay using UV detection is described for the simultaneous measurement of the newer generation anti-epileptic medications lamotrigine, oxcarbazepine (parent drug and active metabolite 10- hydroxycarbazepine), and zonisamide. Detection of all four compounds can be done at 230 nm; however, there is a potential interference with zonisamide in patients on clonazepam therapy. Therefore, the method uses dual wavelength detection: 230 nm for oxcarbazepine and 10-hydroxycarbazepine and 270 nm for lamotrigine and zonisamide. In addition, a simple gas chromatography method using a nitrogen-phosphorus detector is described for the measurement of levetiracetam, another of the recently approved anti-epileptic medications. For both methods, limits of quantitation, linearities, accuracies, and imprecisions cover the therapeutic range for drug monitoring of patients. A wide variety of clinical drugs, including other anti-epileptic drugs, do not interfere with these assays. These procedures would be of special interest to clinical laboratories, particularly due to the limited availability of immunoassays for newer generation anti-epileptic medications and that therapeutic uses of these drugs are expanding beyond epilepsy to other neurologic and psychiatric disorders.
- Published
- 2007
- Full Text
- View/download PDF