Test Code MEX Mexiletine, Serum
Reporting Name
Mexiletine, SUseful For
Assessing achievement of optimal therapeutic mexiletine concentrations
Assessing potential mexiletine toxicity
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
Serum RedSpecimen Required
Patient Preparation: Specimens should only be collected after patient has been receiving mexiletine for at least 3 days. Trough concentrations should be collected just before administration of the next dose.
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube: Red top (serum gel/SST are not acceptable)
Submission Container/Tube: Plastic vial
Specimen Volume: 1.5 mL
Collection Instructions:
1. Draw blood immediately before next scheduled dose.
2. Centrifuge and aliquot serum into a plastic vial within 2 hours of collection.
Specimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum Red | Refrigerated (preferred) | 28 days | |
Ambient | 28 days | ||
Frozen | 28 days |
Reference Values
Trough Value
0.5-2.0 mcg/mL: Therapeutic concentration
>2.0 mcg/mL: Toxic concentration
Day(s) Performed
Monday through Friday
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
80299
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
MEX | Mexiletine, S | 40779-1 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
9245 | Mexiletine, S | 40779-1 |
Report Available
2 to 5 daysReject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Gross icterus | OK |
NY State Approved
YesMethod Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Secondary ID
9245Forms
If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.