Understanding Your Medical Test: A Complete Patient Guide to Testing, Preparation, and What Your Results Mean
This test measures 17-ketogenic steroids in a 24-hour urine sample collected after taking a low-dose dexamethasone medication to evaluate adrenal gland function.
{"The test checks how your adrenal glands respond to dexamethasone medication","Urine is collected for 24 hours after taking dexamethasone pills every 6 hours","It helps diagnose adrenal gland disorders like Cushing's syndrome","Avoid strenuous exercise and certain medications before the test","Results help doctors distinguish between normal adrenal function and adrenal diseases"}
Key facts at a glance
- LOINC
- 1576-8
- Short code
- 17-KGS-DST
- Synonyms
- 17KGS 48h p 500 ug Dex 24h Ur-mRate
- Category
- chemistry
- Sample
- urine
- Container
- 24-hour urine collection container with preservative (typically boric acid or sodium carbonate)
- Units
- N/A
- Ref low
- 3
- Ref high
- 15
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 18 years
- Method
- Gas chromatography-mass spectrometry (GC-MS) or Liquid chromatography-tandem mass spectrometry (LC-MS/MS)
- CPT
- 82533
- SNOMED
- 104617006
- Specimen volume
- Complete 24-hour collection; record total volume (typically 1000-2000 mL)
- Stability
- Room temperature: 24 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C): 30 days
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 72–168 hours
- Order
- routine
What is this test and why has my doctor recommended it for me?
The 17-Ketogenic Steroids test measures the amount of 17-ketogenic steroids in your urine. These are waste products produced when your body breaks down steroid hormones from the adrenal glands. The test is performed as part of a dexamethasone suppression test, which evaluates how your adrenal glands function by checking whether a medication called dexamethasone can suppress (reduce) the production of adrenal hormones.
How is this test performed, and what can I expect during the procedure?
You will take dexamethasone pills (500 micrograms) every 6 hours for 2.5 days as instructed by your doctor. Exactly 48 hours after starting the medication, you will begin collecting your urine in a special container provided by the laboratory. You will continue collecting all urine for exactly 24 hours. During this collection period, keep the container refrigerated or in a cool place. Return the complete collection to the laboratory as soon as possible after the 24-hour period ends.
How should I prepare for the test, and are there any special instructions I need to follow?
Before the test, tell your doctor about all medications you are taking, as some drugs can affect the results. You should avoid strenuous exercise during the collection period, as excessive physical activity can influence hormone levels. Follow your doctor's instructions carefully about when to start taking the dexamethasone pills and when to begin urine collection. Eat and drink normally unless otherwise instructed.
What do my test results mean, and how will my doctor use them to guide my treatment and care?
In healthy individuals, dexamethasone should suppress the production of adrenal hormones, resulting in low levels of 17-ketogenic steroids in the urine. If the levels remain high after taking dexamethasone, it may indicate that your adrenal glands are producing too much hormone, which could suggest conditions like Cushing's syndrome. Your doctor will interpret your results along with other clinical findings to determine if further testing or treatment is needed.
Reference range
Suppression: <2.5 mg/24h (post low-dose dexamethasone); Normal non-suppressed: 3-15 mg/24h (varies by laboratory)N/A
Collect urine for 24 hours starting 48 hours after beginning dexamethasone (500 ug q6h for 2.5 days). Record total collection volume. Keep refrigerated during collection. Avoid vitamin supplements and medications affecting steroid metabolism 48 hours prior. Continue normal fluid intake unless otherwise instructed.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is primarily used to evaluate adrenal gland function and is especially useful in diagnosing Cushing's syndrome, a condition caused by prolonged exposure to high cortisol levels. The dexamethasone suppression test helps distinguish between different causes of elevated adrenal hormones, such as pituitary adenomas (Cushing's disease), adrenal tumors, or ectopic ACTH-producing tumors. It is also used to monitor response to treatment for adrenal disorders.
Normal results show suppressed 17-ketogenic steroid levels after dexamethasone administration, indicating proper adrenal function. Abnormal results showing non-suppressed levels require further investigation to identify the underlying cause of adrenal hormone overproduction.
Frequently asked questions
Why do I need to take dexamethasone for this test?
What happens if I miss a dose of dexamethasone?
Can I collect urine while traveling or at work?
Are there any side effects from the dexamethasone?
How long does it take to get results?
Sources
- 1
- 2
- 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 16, 2026. · Read our editorial policy