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The following is a list of what is included in the item above. Click the test(s) below to view what biomarkers are measured along with an explanation of what the biomarker is measuring.


*Important Information on Lab Test Processing Times: Ulta Lab Tests is committed to informing you about the processing times for your lab tests processed through Quest Diagnostics. Please note that the estimated processing time for each test, indicated in business days, is based on data from the past 30 days across the 13 Quest Diagnostics laboratories for each test. These estimates are intended to serve as a guide and are not guarantees. Factors such as laboratory workload, weather conditions, holidays, and the need for additional testing or maintenance can influence actual processing times. We aim to offer estimates to help you plan accordingly. Please understand that these times may vary, and processing times are not guaranteed. Thank you for choosing Ulta Lab Tests for your laboratory needs.

The Dexamethasone test contains 1 test with 1 biomarker.

Important Note Regarding Dexamethasone Lab Test

Please be advised that the dexamethasone lab test must only be ordered in conjunction with a physician who can provide the appropriate prescription for dexamethasone. The physician will determine the correct dosage and provide specific instructions regarding the timing of medication administration in relation to specimen collection.

It is important to note that the laboratory conducting the dexamethasone test does not supply the dexamethasone medication itself. The medication must be prescribed and obtained separately through a healthcare provider. This ensures that the test is conducted under medically supervised conditions and that the results are accurately interpreted in the context of the prescribed treatment regimen.

The dexamethasone lab test is used primarily to evaluate adrenal gland function by measuring how cortisol levels in the blood change in response to dexamethasone, a synthetic glucocorticoid. This test is commonly referred to as the dexamethasone suppression test. Here’s a brief overview of its two main types:

  1. Low-Dose Dexamethasone Suppression Test: Typically used to diagnose Cushing's syndrome, a condition where the body produces too much cortisol. Patients are given a low dose of dexamethasone, and cortisol levels are measured to see if the medication suppresses the adrenal glands' production of cortisol.

  2. High-Dose Dexamethasone Suppression Test: This version is used to help differentiate between different causes of Cushing’s syndrome, such as pituitary adenomas (small tumors on the pituitary gland) or ectopic ACTH syndrome. A high dose is used to see if cortisol levels can be suppressed in different scenarios.

The procedure generally involves taking dexamethasone orally and measuring cortisol levels in the blood at specific intervals. The results help doctors understand whether the adrenal or pituitary glands are behaving normally.

Reference Range(s)


Baseline Less than 20 ng/dL
1 mg dexamethasone overnight 180-550 ng/dL (8:00-10:00 AM)

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