Mar 24, 2015




Clinical Hub,Tools & Resources,UWHC Lab Test Directory,Toxicology

Carbamazepine and Metabolite

Carbamazepine and Metabolite (HCCARB) Toxicology Lab Test

Name: Carbamazepine and Metabolite

Test Name: Carbamazepine and Metabolite

Health Link Test Code: HCCARB

LIS Test Code: CARB

CPT Code(s): 80156, 80157

Test Component:

Carbamazepine and carbamazepine-10,11-epoxide.

Methodology: Liquid Chromatography

Clinical Information:


Days Performed: Mon-Fri, dayshift.

In-Lab Turnaround Time: 1 day.

Specimen: Blood

Collection Container: Red top

Collection Instructions:

Collect serum sample 15-30 minutes prior to the morning dose.

Collection Volume: 3 mL

Pediatric Collection Volume: 1 mL

Stability Ambient:

2 days

Stability Refridgerated:

3 days

Stability Frozen:

14 days

Sample Analyzed: Serum

Testing Volume: 1 mL

Pediatric Testing Volume: 0.3 mL

Specimen Processing:

Centrifuge. Transfer cell-free serum to plastic vial. Refrigerate.

Specimen Transport:

Transport specimen to laboratory. Transport with coolant pack if coming from clinic location.

Unacceptable Criteria:

Specimens collected in red cap with yellow ring (SST) tubes are not acceptable.


Generally effective therapeutic concentration:  
18 years and up:  


4.0-12.0 mcg/mL 


Carbamazepine-10,11-epoxide metabolite is active and should be 20-30% of parent compound. Carbamazepine-10,11-epoxide level greater than 50% of parent drug level may be toxic.

Interpretation Type: Interpretive Guidelines

Critical Calls: yes

Additional Information:

Result of "BELOW DETECTION" indicates that the result is below the method detection limit of 0.5 mcg/mL. Carbamazepine results greater than 15.0 mcg/mL will be called. Carbamazepine-10,11-epoxide is the principle metabolite of carbamazepine and is an active metabolite whose plasma concentration may be increased in the presence of enzyme inducers, valproic acid, or felbamate.


This test was developed and its performance characteristics determined by the UWHC Clinical Laboratories.  This test meets the standards for clinical testing.  This test should not be regarded as investigational or for research use.  The US Food and Drug Administration (FDA) has not approved or cleared this test; however, the FDA has determined that such clearance or approval is not necessary.