Complete Blood Count (CBC)
This test measures 17-hydroxyprogesterone levels in your blood after an ACTH injection to help diagnose adrenal gland disorders.
{"Measures how your adrenal glands respond to ACTH hormone stimulation","Primary use is to diagnose congenital adrenal hyperplasia (CAH)","Involves a blood draw before and 15 minutes after receiving corticotropin injection","Helps doctors distinguish between different types of adrenal insufficiency"}
Key facts at a glance
- LOINC
- 10964-5
- Short code
- 17-OHP ACTH STIM
- Synonyms
- 17OHP 15M p 250 ug ACTH IM SerPl-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST) 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
- Immunoassay (Chemiluminescence or ELISA)
- CPT
- 82533
- SNOMED
- 313295003
- Specimen volume
- 1-2 mL of serum
- Stability
- Room temperature: 24 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C): 30 days. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 50
- Lipemia max
- 300
- Icterus max
- 20
- TAT
- 24–72 hours
- Order
- routine
A complete blood count (CBC) is a common blood test that measures the different cells in your blood, including red blood cells, white blood cells, and platelets. Your doctor may order it as part of a routine checkup or to help detect infections, anemia, and many other health conditions.
The 17-Hydroxyprogesterone (17-OHP) test after ACTH stimulation measures the level of 17-hydroxyprogesterone in your blood before and after your adrenal glands are stimulated with corticotropin (ACTH). This helps doctors evaluate how well your adrenal glands are functioning.
A healthcare professional will draw a small sample of blood, usually from a vein in your arm. The site is cleaned with an antiseptic, a band is placed around your upper arm, and a thin needle collects the sample into a small tube. The blood draw typically takes only a few minutes.
First, a blood sample is taken from your arm. Then, you will receive an injection of synthetic ACTH (corticotropin) into your muscle. After exactly 15 minutes, another blood sample is drawn. Both samples are sent to a laboratory to measure 17-OHP levels.
In most cases, no special preparation is needed for a CBC, and you can eat and drink normally beforehand. However, if your doctor has ordered additional tests at the same time, such as a fasting blood glucose or lipid panel, you may be asked to avoid food and drink for 8 to 12 hours before the draw.
Your doctor will provide specific instructions. Generally, you may need to fast (not eat or drink except water) for a certain period before the test. Tell your doctor about all medications you are taking, as some medicines can affect test results.
You may feel a quick pinch or sting when the needle goes in, and some people notice mild soreness or a small bruise at the puncture site afterward. These effects usually fade within a day, and you can return to your normal activities right after the blood sample is collected.
You may feel a brief sting when the needle is inserted to draw blood. The ACTH injection may cause a brief burning sensation at the injection site. Some people may experience flushing, increased heart rate, or mild dizziness after the injection, but these effects are usually temporary.
Reference range
Normal response: <10 ng/dL (0.3 nmol/L) at 15 minutes post-ACTH stimulation. Values >10 ng/dL suggest 21-hydroxylase deficiency. Reference range may vary by laboratory methodology.N/A
No fasting required. Blood sample collected 15 minutes after intramuscular injection of 250 mcg corticotropin (ACTH). Patient should inform healthcare provider of any corticosteroid or hormone therapy medications. Avoid stress and strenuous exercise before test.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is primarily used to diagnose and differentiate types of congenital adrenal hyperplasia (CAH), a genetic disorder affecting adrenal hormone production. It also helps distinguish between adrenal insufficiency (Addison's disease) and other adrenal disorders. Abnormally high 17-OHP levels after stimulation suggest CAH, while normal or low levels may indicate other adrenal conditions.
Frequently asked questions
Why do I need an ACTH stimulation test?
How long does the test take?
Are there any risks with this test?
When will I get my 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 10, 2026. · Read our editorial policy