Test Name: Lamotrigine
Health Link Test Code: XLAMO
LIS Test Code: LAMO
CPT Code(s): 80175
Methodology: Liquid Chromatography
Days Performed: Daily, dayshift.
In-Lab Turnaround Time: 1 day.
Collection Container: Red top
Collect specimen for trough level prior to next dose.
Collection Volume: 3 mL
Pediatric Collection Volume: 1 mL
Sample Analyzed: Serum
Testing Volume: 1 mL
Centrifuge. Transfer serum to clean tube. Refrigerate.
Transport specimen to laboratory. Transport with coolant pack if coming from clinic location.
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
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.