How It Is Done
The health professional drawing blood
- Wrap an elastic band around your upper arm to
stop the flow of blood. This makes the veins below the band larger so it is
easier to put a needle into the vein.
- Clean the needle site with
- Put the needle into the vein. More than one needle stick
may be needed.
- Attach a tube to the needle to fill it with
- Remove the band from your arm when enough blood is
- Put a gauze pad or cotton ball over the needle site as
the needle is removed.
- Put pressure on the site and then put on a
How It Feels
The blood sample is taken from a vein in
your arm. An elastic band is wrapped around your upper arm. It may feel tight.
You may feel nothing at all from the needle, or you may feel a quick sting or
There is very little chance of a problem from
having a blood sample taken from a vein.
- You may get a small bruise at the site. You can
lower the chance of bruising by keeping pressure on the site for several
- In rare cases, the vein may become swollen after the blood
sample is taken. This problem is called phlebitis. A warm compress can be used
several times a day to treat this.
- Ongoing bleeding can be a
problem for people with bleeding disorders. Aspirin, warfarin (Coumadin), and
other blood-thinning medicines can make bleeding more likely. If you have
bleeding or clotting problems, or if you take blood-thinning medicine, tell
your doctor before your blood sample is taken.
- Bruising may be more
likely in people with high ACTH and cortisol levels.
An adrenocorticotropic hormone test
measures the level of
adrenocorticotropic hormone (ACTH) in the blood.
Results of an ACTH test are usually available in a few
The normal values listed here—called a reference range—are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what's normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab.
Normal ACTH levels
Less than 80
pg/mL or less than 18
Less than 50 pg/mL or less than 11
High levels of ACTH may be caused
- Emotional or physical stress (such as recent
surgery or severe pain).
- Diseases such as
Addison's disease (failure of the adrenal glands ),
Cushing's disease (a tumor of the
pituitary gland ), or a tumor outside the pituitary (such as in the lung).
Low levels of ACTH may be caused
- Damage to the pituitary gland from surgery,
radiation, stroke, head injury, or a tumor.
- An increased amount of
cortisol from a tumor in the adrenal glands (Cushing's syndrome).
- Corticosteroid medicines.
ACTH and cortisol levels in specific conditions