Analytic Time
5 - 9 days
Soft Order Code
FFTRZ
Test Updated:
Synonyms
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Test Overview
Test Methodology
Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)
Test Usage
Monitoring for optimal therapeutic concentrations or patient compliance.
Reference Range
800 – 1600 ng/mL
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Specimen Requirements
Offsite Collection Instructions
Collect specimen in a red top tube; do not use SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate.
Normal Volume
1 mL serum
Minimum Volume
0.6 mL serum
Billing Information
CPT Code
80338
Pro Fee Code
LOINC
4064-2