Carbamazepine Epoxide and Total

The therapeutic range is based on serum pre-dose (trough) draw at steady-state concentration. The carbamazepine metabolite, Carbamazepine-10, 11-Epoxide, has anticonvulsant activity and a proposed therapeutic range of 0.4-4 µg/mL. 

A rare, adverse drug reaction to carbamazepine therapy includes Stevens-Johnson syndrome or toxic epidermal necrolysis. Patients of Asian ancestry with the presence of the HLA-B*15:02 have an increased risk for this carbamazepine-induced, life-threatening reaction. Pharmacogenetic testing for HLA-B*15:02 is recommended prior to treatment for patients at risk of carbamazepine hypersensitivity. This information has been included in the FDA-approved label for carbamazepine (<https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm?event=overview.process&varApplNo=016608>) and in the guideline from the Clinical Pharmacogenetics Implementation Consortium (https://www.pharmgkb.org/guidelines). (HLA-B*15:02 Genotyping, Carbamazepine Hypersensitivity, ARUP test code 2012049.)

A combination of therapeutic drug monitoring with HLA-B*15:02 pharmacogenetics genotyping may benefit patients at increased risk of developing carbamazepine-induced adverse events due to rare genotypes other than the HLA-B*15:02 variant allele.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.