Days Set Up
Analytic Time

5 - 20 days

Soft Order Code

Test Updated:


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Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

Learn about how to properly label and where to ship specimens.

Order Kits and Supplies

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

Test FAQ

Visit our provider FAQ and learn about common questions to ordering tests.

Test Overview

Test Methodology

High-pressure liquid chromatography/tandem mass spectrometry (HPLC/MS-MS)

Test Usage
Reference Range

Adults: <30 ng/dL the morning after 1mg dexamethasone dose the previous evening
140 - 295 ng/dL the morning aftr (4 x 2 mg doses) the previous day

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Collection Onsite

Draw blood in a plain red top tube. (SST is acceptable) and send to Specimen Processing.

Collection Offsite

Draw blood in a plain, red-top tube(s). Spin down and send 3 mL of serum frozen in a plastic vial. SST is acceptable, but must be aliquoted into a screw capped plastic tube.

Red Top Tube
Normal Volume
3 mL serum
Minimum Volume
1 mL serum (min volume does not allow for repeat analysis)

Billing Information

CPT Code
Pro Fee Code

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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.