High Turbulence Liquid Chromatography–Tandem Mass Spectrometry (HTLC-MS/MS)
Therapeutic Drug Monitoring
Therapeutic: >40 mcg/mL; Elimination:
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Days Test Performed
Monday, Wednesday, Friday
3 - 7 days
Soft Order Code
Leflunomide Metabolite Serum (Sendout)
Mayo LEFLU (60292)
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Offsite Collection Instructions
Collect specimen in a red top (preferred) or SST tube. Centrifuge and aliquot serum into a plastic vial within 2 hours of collection. Store and transport at room temperature (preferred); specimen may be stored refrigerated or frozen for up to 14 days.
1 mL serum
0.3 mL serum
Test sent to Mayo Medical Laboratories.