Growth Hormone (GH)

What is growth hormone (GH)?

Growth hormone is a protein hormone produced by the pituitary gland that stimulates growth, cell reproduction, and cell regeneration in humans and other animals. It is also involved in the metabolism of carbohydrates, fats, and proteins.

What is GH testing used for?

GH testing is used to diagnose conditions related to excess or deficiency of growth hormone. It may be used to diagnose GH deficiency in children, acromegaly (excess GH production) in adults, or to monitor GH therapy in people with GH deficiency.

How is GH tested?

GH is typically measured through a blood test. The blood sample is taken in a healthcare provider's office or a laboratory and sent to a laboratory for analysis.

What is a normal range for GH levels in the blood?

The normal range for GH levels in the blood varies depending on the laboratory and the specific test used. In general, normal GH levels are less than 5 nanograms per milliliter (ng/mL) in adults and less than 10 ng/mL in children.

What can cause abnormal GH levels?

Abnormal GH levels can be caused by a variety of conditions, including pituitary tumors, head injuries, hypothalamus disorders, and stress. In addition, certain medications, such as steroids and estrogens, can affect GH levels.

What are the symptoms of GH deficiency in children?

Symptoms of GH deficiency in children may include slow growth, short stature, and delayed puberty.

What are the symptoms of excess GH production in adults (acromegaly)?

Symptoms of excess GH production in adults may include thickening of the skin, bones, and organs; changes in facial features; and an enlarged tongue.

How is GH deficiency or excess treated?

GH deficiency may be treated with GH replacement therapy, which involves injections of synthetic GH. Excess GH production may be treated with medications, surgery, or radiation therapy to remove the pituitary tumor causing the excess production.