Adrenocorticotropic Hormone (ACTH)
This test determines the concentration of adrenocorticotropic hormone (ACTH) in the blood. ACTH is a hormone that is produced by the pituitary gland, which is located near the base of the brain. ACTH regulates the synthesis of another hormone known as cortisol. The adrenal glands are two tiny glands positioned above the kidneys, producing cortisol. Cortisol is essential in:
- Combat illness by responding to stress.
- Control blood sugar levels.
- Maintain normal blood pressure.
- Control your metabolism, which is how your body consumes food and energy.
If Cortisol levels are too high or too low might lead to major health concerns.
What is it used for?
An ACTH test is frequently used in conjunction with a cortisol test to identify pituitary or adrenal gland problems, such as:
- Cushing's syndrome
- Cushing's disease
- Addison's disease
What is the need for an ACTH test?
This test may be required if you experience symptoms of more or less cortisol.
Cortisol overdose symptoms include:
- Increase in weight
- The buildup of fat in the shoulder area
- Pink stretch marks on the abdomen, thighs, and/or breasts
- Skin bruises
- Increased body hair
- Muscle weakness
Symptoms of less cortisol include:
You may also require this test if you have hypopituitarism symptoms. The following symptoms may occur depending on the severity of the disease:
What happens during an ACTH test?
A tiny needle will be used by a healthcare provider to draw blood from a vein in your arm. Following the insertion of the needle, a little quantity of blood will be collected in a test tube or vial. When the needle goes in or out, you may feel a slight sting. This normally takes five minutes.
How to prepare for the test?
Before testing, you may need to fast (not eat or drink) overnight. Since cortisol levels fluctuate throughout the day, tests are normally performed early in the morning.
Is there any risk in the test?
Having a blood test poses no risk or danger. You may experience some discomfort or bruising where the needle was inserted, but mostly it goes soon.
What do the findings imply?
ACTH test results are frequently compared to cortisol test results and may reveal one of the following:
- Elevated ACTH and cortisol levels may indicate Cushing's illness.
- Low ACTH and high cortisol levels may indicate Cushing's disease or an adrenal gland tumor.
- High ACTH and low cortisol levels may indicate Addison's disease.
- ACTH and cortisol levels are low may indicate hypopituitarism.
Consult your doctor if you have any doubts or confusion on your results.
Important information to know about ACTH testing?
To detect Addison's disease and hypopituitarism, an ACTH stimulation test is occasionally used instead of an ACTH test. An ACTH stimulation test is a simple blood test that compares cortisol levels before and after an ACTH injection.