What is being analysed?
The ACTH test measures levels of ACTH in the blood. ACTH is a hormone that stimulates the production of cortisol in the adrenal glands.
What does the result mean?
The results of the ACTH test can help diagnose disorders of the pituitary and adrenal glands, such as Addison’s disease, Cushing’s syndrome, and congenital adrenal hyperplasia.
Why is the test done?
The ACTH test is performed to diagnose and monitor diseases that affect cortisol levels in the body. These conditions include diseases of the pituitary gland and adrenal glands.
When is the test done?
Your healthcare provider may order an ACTH test if you have symptoms of a pituitary or adrenal gland disorder, such as fatigue, muscle weakness, weight loss, low blood pressure, dizziness, nausea, vomiting, abdominal pain, darkening of the skin, and changes in body or hair distribution.
What sample is required?
The ACTH test is performed with a blood sample.
Is any preparation needed?
No special preparation is required.
What are the normal values?
Normal ACTH values in blood vary depending on the time of day the test is performed. Normal ACTH values in the morning are 6 to 76 pg/mL (1.3 to 16.7 pmol/L) in adults.
What does it mean to have altered values?
ACTH levels can be higher or lower than normal due to a variety of disorders, such as Addison’s disease, Cushing’s syndrome, and congenital adrenal hyperplasia. Your healthcare provider will interpret the results of the ACTH test in the context of your symptoms and other test results.