Mar 24, 2015




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


Lamotrigine (XLAMO) Toxicology Lab Test

Name: Lamotrigine

Test Name: Lamotrigine

Health Link Test Code: XLAMO

LIS Test Code: LAMO

CPT Code(s): 80175

Methodology: Liquid Chromatography

Clinical Information:


Days Performed: Daily, dayshift.

In-Lab Turnaround Time: 1 day.

Specimen: Blood

Collection Container: Red top

Collection Instructions:

Collect specimen for trough level prior to next dose.

Collection Volume: 3 mL

Pediatric Collection Volume: 1 mL

Stability Ambient:

6 days

Stability Refridgerated:

7 days

Stability Frozen:

14 days

Sample Analyzed: Serum

Testing Volume: 1 mL

Specimen Processing:

Centrifuge. Transfer serum to clean tube. 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.


Therapeutic concentrations of lamotrigine have not been established. Dosing should be guided by clinical response. In general, a trough concentration of 2.0-15.0 mcg/mL is considered effective for individuals 18 years old and up.

Interpretation Type: Interpretive Guidelines

Critical Calls: yes

Additional Information:

A result of "BELOW DETECTION" indicates that the result is below the method detection limit of 0.5 mcg/mL. A pharmacodynamic interaction may occur with carbamazepine, phenytoin, or phenobarbital, lowering blood levels of lamotrigine. Valproic acid slows lamotrigine metabolism, thus raising blood levels.


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.