17ohp1hpacthserplmcnc
This blood test measures 17-hydroxyprogesterone levels after a corticotropin (ACTH) stimulation to help diagnose adrenal gland disorders.
{"Measures 17-OHP hormone levels 1 hour after ACTH injection","Used mainly to diagnose congenital adrenal hyperplasia (CAH)","Helps distinguish between different types of adrenal disorders","Involves two blood draws: one before and one after ACTH stimulation","Results help doctors plan appropriate treatment"}
Key facts at a glance
- LOINC
- 101312-7
- Short code
- 17OHP-ACTH-1HR
- Synonyms
- 17OHP 1h p ACTH SerPl-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Serum Separator Tube (SST/Gold top) or plain red top tube
- Units
- N/A
- Ref low
- 1
- Ref high
- 10
- Critical range
- — – 100 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- Chemiluminescent Immunoassay (CLIA) or Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
- CPT
- 82533
- SNOMED
- 3651005
- Specimen volume
- 1.0-2.0 mL serum minimum
- Stability
- Room temperature: 24 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 50
- Lipemia max
- 300
- Icterus max
- 20
- TAT
- 24–72 hours
- Order
- routine
What is this test?
The 17-Hydroxyprogesterone (17-OHP) test after ACTH stimulation is a specialized blood test that measures how your adrenal glands respond to a hormone called adrenocorticotropic hormone (ACTH). First, a small amount of ACTH is injected to stimulate your adrenal glands. Then, blood is drawn 1 hour later to measure the 17-OHP level. This test helps doctors understand how well your adrenal glands are working and can identify certain hormonal disorders.
How is the test performed?
The test involves several steps: 1) A healthcare provider will first draw a baseline blood sample. 2) Then, synthetic ACTH is injected into your arm. 3) After exactly 1 hour, another blood sample is drawn. 4) Both samples are sent to a laboratory to measure 17-OHP levels. The difference between the two measurements helps your doctor assess your adrenal function.
Why might I need this test?
Your doctor may order this test if you or your child have symptoms suggesting a adrenal gland problem, such as early puberty, irregular periods, excessive hair growth, or signs of hormonal imbalance. It is also commonly used to screen for and diagnose congenital adrenal hyperplasia (CAH), a genetic condition affecting adrenal hormone production.
What do the results mean?
Normal results show a modest increase in 17-OHP after ACTH stimulation. Significantly elevated 17-OHP levels after stimulation typically indicate congenital adrenal hyperplasia (CAH). Mildly elevated levels may suggest other forms of adrenal insufficiency. Your doctor will interpret your results based on your specific situation, symptoms, and other test findings.
Reference range
Normal response: Post-stimulation 17-OHP typically <10 ng/dL (0.3 nmol/L). Borderline: 10-15 ng/dL. Abnormal (consistent with CAH): >15 ng/dL; often >100 ng/dL in classic 21-hydroxylase deficiencyN/A
No fasting required. Test is performed 1 hour after intravenous or intramuscular administration of 250 mcg cosyntropin (ACTH). Morning collection preferred (8-10 AM) when endogenous cortisol is at peak. Avoid corticosteroid medications prior to testing unless specifically instructed by physician.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Frequently asked questions
Do I need to fast before this test?
Are there any risks or side effects?
How long does the test take?
When will I get my results?
What happens if my results are abnormal?
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 10, 2026. · Read our editorial policy