Blood Test (Laboratory Testing): What to Expect Before, During, and After Your Blood Draw
A blood test measuring 11-hydroxyandrostenedione levels 30 minutes after corticotropin (ACTH) injection to evaluate adrenal gland function.
{"This test checks how well your adrenal glands respond to ACTH stimulation","It helps diagnose adrenal disorders like congenital adrenal hyperplasia (CAH)","A small amount of ACTH is injected, and blood is drawn 30 minutes later to measure hormone levels","The test is typically done in the morning after an overnight fast","Results help doctors distinguish between different types of adrenal gland disorders"}
Key facts at a glance
- LOINC
- 50069-4
- Short code
- 11-OH-A-dione ACTH stim
- Synonyms
- 11OH-Ad 30M p 250 ug ACTH SerPl-sCnc
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST) or plain red top tube
- Units
- N/A
- Ref low
- 4.5
- Ref high
- 12
- Critical range
- 3 N/A – —
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- Liquid chromatography-tandem mass spectrometry (LC-MS/MS) or Immunoassay
- CPT
- 82533
- SNOMED
- 31247009
- Specimen volume
- 1-2 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
- 40
- TAT
- 24–72 hours
- Order
- routine
A blood test is a common laboratory procedure in which a small sample of your blood is collected and analyzed to evaluate your overall health, screen for medical conditions, and help your doctor diagnose, treat, or monitor an illness.
The 11-Hydroxyandrostenedione (11-OHA) test is a specialized blood test that measures the level of 11-hydroxyandrostenedione in your blood 30 minutes after receiving an injection of corticotropin (ACTH). ACTH is a hormone produced by the pituitary gland that stimulates the adrenal glands to produce hormones. This test evaluates how well your adrenal glands respond to this stimulation.
A trained healthcare professional will wrap a band around your upper arm, clean the skin at the puncture site, and insert a thin needle into a vein, usually in your arm or hand, to collect a small amount of blood into one or more tubes.
The test involves several steps: First, a baseline blood sample is taken to measure your initial hormone levels. Then, a small amount of synthetic ACTH (250 micrograms) is injected into your arm. After exactly 30 minutes, another blood sample is drawn to measure how your hormone levels have changed in response to the ACTH stimulation.
Follow your provider's instructions carefully, since some blood tests require fasting for 8 to 12 hours beforehand. Drink plenty of water, wear sleeves that roll up easily, and tell your care team about any medications, supplements, or bleeding problems you have.
Follow these preparation guidelines: Fast overnight (8-12 hours) before the test. Inform your doctor about all medications you are taking, as certain medications (especially steroids and hormone treatments) may affect results. The test is usually performed in the morning because hormone levels naturally vary throughout the day. Tell your doctor if you are pregnant or have any known adrenal or pituitary conditions.
You may feel a quick pinch or mild sting when the needle goes in, and some people notice brief throbbing or slight soreness at the puncture site afterward, but the discomfort is usually minimal and fades within a few minutes.
You may feel a brief sting when the needle is inserted for the blood draw or the ACTH injection. Some people may experience temporary flushing, increased heart rate, or mild dizziness after the ACTH injection. These effects are usually mild and subside quickly. The test is generally well-tolerated by most patients.
Reference range
Reference range: 4.5-12.0 nmol/L at 30 minutes post 250 ug corticotropin stimulation. Peak response typically occurs 30-60 minutes after ACTH administration. Response may vary based on clinical indication and reference laboratory.N/A
Patient should fast overnight (8-12 hours) before test. Baseline sample collected, then 250 ug cosyntropin (ACTH) administered intramuscularly or intravenously. Second sample collected exactly 30 minutes post stimulation. Inform patient of potential for mild discomfort at injection site. Continue usual medications unless directed otherwise by physician.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
The 11-OHA test is primarily used to evaluate adrenal gland function and diagnose disorders affecting adrenal hormone production. Elevated 11-OHA levels after ACTH stimulation may indicate conditions such as 11-beta-hydroxylase deficiency (a form of congenital adrenal hyperplasia), which causes the body to produce excess androgen hormones. This can lead to early puberty in children, irregular menstrual periods in women, and other hormonal imbalances.
The test also helps distinguish between different types of adrenal disorders. For example, it can help differentiate between adrenal insufficiency (Addison's disease) and other conditions causing similar symptoms. Additionally, it may be used to evaluate patients with ambiguous genitalia, premature puberty, or hirsutism (excessive hair growth) to identify the underlying cause of hormonal abnormalities.
Normal response to ACTH stimulation shows a significant increase in 11-OHA levels. An blunted or absent response may indicate adrenal insufficiency or other adrenal disorders. Your doctor will interpret your results in context with other clinical findings and possibly additional tests to determine the appropriate diagnosis and treatment plan.
Frequently asked questions
Why is the test done 30 minutes after ACTH injection?
Are there any risks or side effects?
How long does it take to get results?
Do I need to stop medications before the test?
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