Carbamazepine, Serum or Plasma

Casandra

Casandra Test Code LC48068Version 1 (DRAFT)

Performing Lab

Lab LabcorpLab Test ID 007419CPT Code 80156

Carbamazepine, Serum or Plasma

Also known as: Carbatrol®, Epitol®, Equetro®, Tegretol®

Clinical Use

Order Test

Use

This heterocyclic (iminostilbene) compound has potent antiepileptic properties and is effective alone or with other antiepileptic drugs in partial seizures, especially complex partial seizures, generalized tonic-clonic seizures, and combinations of these seizure types. Carbamazepine generally is ineffective for absence, myoclonic, and atonic seizures. In children with symptomatic generalized epilepsy and continuous spike-and-wave discharge, these seizure types may develop or tonic-clonic seizures may increase in frequency with use of carbamazepine. It has also been noted1 that the dose of carbamazepine cannot be used as a reliable index for predicting the serum concentration of either total or free carbamazepine serum concentrations in children with epilepsy.

Special Instructions

Trough levels should be drawn immediately prior to the next dose. Due to variability in absorption, multiple level determinations may be necessary. Gel-barrier tubes should be avoided as they may absorb the drug, leading to decreased levels.

Limitations

Carbamazepine cannot be used as a reliable index for predicting serum concentrations in children with epilepsy. Variability in absorption may cause trough levels not to represent the lowest drug level during the dosing interval. The use of gel-barrier tubes is discouraged due to potential absorption issues. Carbamazepine can induce hepatic enzymes leading to decreased serum levels of many other drugs, and serum levels should be interpreted with caution in polypharmacy contexts.

Test Details