Skip to content
    Font Size
    A
    A
    A

    Growth Hormone

    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. To learn more, 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 hormone.

    Citations

    1. Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.

    Other Works Consulted

    • Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.

    • Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.

    • Pagana KD, Pagana TJ (2010). Mosby’s Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.

    WebMD Medical Reference from Healthwise

    Last Updated: November 14, 2014
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

    Hot Topics

    WebMD Video: Now Playing

    Click here to wach video: Dirty Truth About Hand Washing

    Which sex is the worst about washing up? Why is it so important? We’ve got the dirty truth on how and when to wash your hands.

    Click here to watch video: Dirty Truth About Hand Washing

    Popular Slideshows & Tools on WebMD

    disciplining a boy
    Types, symptoms, causes.
    fruit drinks
    Eat these to think better.
    embarrassed woman
    Do you feel guilty after eating?
    diabetes supply kit
    Pack and prepare.
    Balding man in mirror
    Treatments & solutions.
    birth control pills
    Which kind is right for you?
    Remember your finger
    Are you getting more forgetful?
    sticky notes on face
    10 tips to clear your brain fog.
    Close up of eye
    12 reasons you're distracted.
    woman biting a big ice cube
    Habits that wreck your teeth.
    apple slices with peanut butter
    What goes best with workouts?
    Pink badge on woman chest to support breat cancer
    Myths and facts.

    Pollen counts, treatment tips, and more.

    It's nothing to sneeze at.

    Loading ...

    Sending your email...

    This feature is temporarily unavailable. Please try again later.

    Thanks!

    Now check your email account on your mobile phone to download your new app.

    Women's Health Newsletter

    Find out what women really need.