Analytic Time

5 - 9 days

Soft Order Code
FFTRZ

Test Updated:

Synonyms
 

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Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

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MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

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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

Collection Onsite

Collect specimen in a red top tube; do not use SST tube.

Collection Offsite

Collect specimen in a red top tube; do not use SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate.

Yellow Top Tube
Red Top Tube
Normal Volume
1 mL serum
Minimum Volume
0.6 mL serum

Billing Information

CPT Code
80338
Pro Fee Code
 
LOINC
4064-2

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.