4 - 8 days
Test Updated:
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Test Overview
Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS)
Therapeutic drug monitoring.
< 235 ng/mL
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Specimen Requirements
Collect specimen in a red top tube; do not use SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate. For maximum clinical significance, usual sampling times are Peak: 1 hour after administration of oral dose or Trough: immediately before next dose is given. Indicate whether specimen is Peak, Trough, or Random level.