There is very little chance of a problem from
having 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.
A growth hormone (GH) test measures the
amount of human growth
hormone (GH) in the blood.
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.
- High GH values may mean
acromegaly is present. These conditions are caused by
a noncancerous tumor in the pituitary gland (adenoma). Insulin-like growth
factor 1 (IGF-1) levels should also be high.
- High GH levels may also
be caused by
diabetes, kidney disease, or starvation. These
conditions do not cause high IGF-1 levels.
What Affects the Test
Reasons you may not be able to
have the test or why the results may not be helpful include:
What To Think About
- Normal levels of growth hormone (GH) change
during the day so other tests may be done to confirm the results of a GH test.
Other tests can show whether low levels of GH (which can be normal) mean the
pituitary gland is not working correctly.
- IGF-1 blood levels are often done at the
same time as a GH test. A high level of IGF-1 with a high level of GH generally
means acromegaly is present. In this case,
magnetic resonance imaging (MRI) is done to look at
the pituitary gland. For more information, see the topic
Magnetic Resonance Imaging (MRI) of the Head.
- The growth hormone suppression test (also called the
glucose loading test) measures the level of GH in the blood before and after a
person drinks fluid with a large amount of sugar (glucose) in it. Normally, the
amount of GH drops to less than 1 ng/mL after drinking the glucose. Levels of
GH that stay high may mean acromegaly is present.
- The growth
hormone stimulation test measures the level of GH in the blood before and after
insulin or arginine is given in a vein (intravenously)
in the arm. No detectable growth hormone can be found for people with normal pituitary function. A growth hormone
stimulation test may be used to see if a person lacks GH. Normally, the amount
of GH increases after insulin or arginine. A GH level that does not increase
after the insulin or arginine is given may mean the person lacks growth