Cortisol, Post-Dexamethasone Stimulation (Serum)
This test measures your cortisol levels in blood after you receive a dose of dexamethasone, a medication that suppresses natural cortisol production. It helps assess how well your body responds to stress and regulates hormone balance.
["This test checks your body’s ability to produce cortisol after a medication challenge."]
Key facts at a glance
- LOINC
- 102024-7
- Short code
- Cortis 60M post dose glucagon SerPl-sCnc
- Synonyms
- Cortis 60M post dose glucagon SerPl-sCnc
- Category
- hormone
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 17
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your doctor may order this test if you have symptoms like unexplained weight changes, fatigue, or signs of hormone imbalance. It’s also used to diagnose conditions like Cushing’s syndrome or adrenal insufficiency, or to evaluate how well certain treatments are working.
What to Expect Before the Test
You’ll receive an injection of dexamethasone, a steroid-like medication, and then blood will be drawn at specific times to measure cortisol levels. Follow your doctor’s instructions carefully about fasting or avoiding certain foods/drinks before the test.
What Happens During the Test
After the dexamethasone dose, blood samples will be taken at intervals (often 30 minutes, 1 hour, and later) to check cortisol levels. This helps your doctor see how your body reacts to the medication.
What the Results Mean
Results help determine if your adrenal glands are functioning normally or if they’re overproducing cortisol. Abnormal results may indicate conditions like adrenal tumors, pituitary issues, or other hormonal disorders.
Reference range
NCBI: NSE 0-17 ng/mLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: This test is critical for diagnosing conditions where cortisol production is too high (e.g., Cushing’s syndrome) or too low (e.g., adrenal insufficiency). It also guides treatment decisions for conditions like chronic stress or hormone therapy.
Short name
Cortisol Stimulation Test
Frequently asked questions
How long does the test take?
Will I feel any side effects from the dexamethasone?
Can I eat or drink normally before the test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy