Hypopituitarism is a condition in which the pituitary gland does not produce normal amounts of some or all of its hormones.
The pituitary gland is a small structure that is located just below the brain. It is attached by a stalk to the hypothalamus. The hypothalamus is the area of the brain that controls the pituitary gland's function.
The hormones released by the pituitary gland (and their functions) are:
In hypopituitarism, there is a lack of one or more pituitary hormones. Lack of a hormone leads to loss of function in the gland or organ the hormone controls. For example, lack of TSH leads to loss of normal function of the thyroid gland.
Hypopituitarism may be caused by:
Sometimes, hypopituitarism is due to uncommon immune system or metabolic diseases, such as:
Hypopituitarism is also a rare complication caused by severe bleeding during pregnancy. The loss of blood leads to tissue death in the pituitary gland. This condition is called Sheehan syndrome.
Certain medicines can also suppress pituitary function. The most common drugs are glucocorticoids (such as prednisone and dexamethasone), which are taken for inflammatory and immune conditions. Drugs used to treat prostate cancer can also lead to low pituitary function.
Symptoms of hypopituitarism include any of the following:
Symptoms may develop slowly and may vary greatly, depending upon:
Other symptoms that may occur with this disease:
To diagnose hypopituitarism, there must be low hormone levels due to a problem with the pituitary gland. The diagnosis must also rule out diseases of the organ that is affected by this hormone.
Tests may include:
Level of a pituitary hormone may be high in the bloodstream if you have a pituitary tumor that is producing too much of that hormone. The tumor may crush other cells of the pituitary, leading to low levels of other hormones.
If hypopituitarism is caused by a tumor, you may need surgery to remove the tumor. Radiation therapy may also be needed.
You will need lifelong hormone medicines to replace hormones that are no longer made by organs under the control of the pituitary gland. These may include:
Drugs are also available to treat related infertility in men and women.
Hypopituitarism is usually permanent. It requires lifelong treatment with one or more medicines. But you can expect a normal life span.
Side effects of medicines to treat hypopituitarism can develop. However, do not stop any medicine on your own without talking with your health care provider first.
Call your provider if you develop symptoms of hypopituitarism.
In most cases, the disorder is not preventable. Awareness of risk, such as from taking certain medicines, may allow early diagnosis and treatment.
Reviewed By: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.