Hypopituitarism is a rare disorder in which your pituitary gland either fails to produce one or more of its hormones or doesn't produce enough of them.
The pituitary gland is a small bean-shaped gland situated at the base of your brain, behind your nose and between your ears. Despite its size, this gland secretes hormones that influence nearly every part of your body.
In hypopituitarism, you have a short supply of one or more of these pituitary hormones. This deficiency can affect any number of your body's routine functions, such as growth, blood pressure and reproduction.
You'll likely need medications for the rest of your life to treat hypopituitarism, but your symptoms can be controlled.
Hypopituitarism is often progressive. Although the signs and symptoms can occur suddenly, they more often develop gradually. They are sometimes subtle and may be overlooked for months or even years.
Signs and symptoms of hypopituitarism vary, depending on which pituitary hormones are deficient and how severe the deficiency is. They may include:
- Weight loss
- Decreased sex drive
- Sensitivity to cold or difficulty staying warm
- Decreased appetite
- Facial puffiness
- Hot flashes, irregular or no periods, loss of pubic hair, and inability to produce milk for breast-feeding in women
- Decreased facial or body hair in men
- Short stature in children
When to see a doctor
See your doctor if you develop signs and symptoms associated with hypopituitarism.
Contact your doctor immediately if certain signs or symptoms of hypopituitarism develop suddenly or are associated with a severe headache, visual disturbances, confusion or a drop in blood pressure. Such signs and symptoms could represent sudden bleeding into the pituitary gland (pituitary apoplexy), which requires prompt medical attention.
Hypopituitarism may be the result of inherited disorders, but more often it's acquired. Hypopituitarism frequently is triggered by a tumor of the pituitary gland. As a pituitary tumor increases in size, it can compress and damage pituitary tissue, interfering with hormone production. A tumor can also compress the optic nerves, causing visual disturbances.
The cause of hypopituitarism can also be other diseases and events that damage the pituitary, such as:
- Head injuries
- Brain or pituitary tumors
- Brain surgery
- Radiation treatment
- Autoimmune inflammation (hypophysitis)
- Infections of the brain, such as meningitis
- Infiltrative diseases, such as sarcoidosis, which is an inflammatory disease occurring in various organs; Langerhans cell histiocytosis, in which abnormal cells cause scarring in numerous parts of the body, such as the lungs and bones; and hemochromatosis, which causes excess iron deposition in the liver and other tissues
- Severe loss of blood during childbirth, which may cause damage to the front part of the pituitary gland (Sheehan syndrome or postpartum pituitary necrosis)
- Genetic mutations resulting in impaired pituitary hormone production
Diseases of the hypothalamus, a portion of the brain situated just above the pituitary, also can cause hypopituitarism. The hypothalamus produces hormones of its own that directly affect the activity of the pituitary.
In some cases, the cause of hypopituitarism is unknown.