Test Overview
Test Methodology

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Test Usage

Monitor therapeutic drug level

Reference Range *

Therapeutic: 0.5 - 2.0 mcg/mL; Toxic: greater than 2 mcg/mL.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Details
Days Set Up
Monday - Saturday
Analytic Time

2 - 6 days

Soft Order Code
MMLR
Laboratory
Sendout
Reference Laboratory
Mayo MEX (9245)
Section
Special Testing
Specimen Requirements
Collection Instructions

Collect a trough specimen in a red top tube after patient has been receiving Mexiletine for at least 3 days; do not use SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate.

Rejection Criteria
SST tube not acceptable.
Yellow Top Tube
Red Top Tube
Normal Volume
1.5 mL serum
Minimum Volume
0.5 mL serum
Additional Information

Test sent to Mayo Clinic Laboratories.

Billing
CPT Code
80299
Fee Code
20039
LOINC
3819-0
Resources