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Overview of the Pituitary Gland


The Manual's Editorial Staff

Last full review/revision Feb 2021| Content last modified Feb 2021
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What is the pituitary gland?

The pituitary gland is a pea-sized bit of tissue at the bottom of your brain. Glands are organs that make and release hormones into your blood. Hormones are chemicals that stimulate other cells or tissues into action. The pituitary gland puts out many different hormones. Each pituitary hormone controls a different gland and body function.

The pituitary gland is controlled by a part of the brain called the hypothalamus.

Locating the Pituitary Gland

Locating the Pituitary Gland

What are pituitary hormones?

Each pituitary hormone controls different glands and body functions.

Pituitary hormones include:

  • ACTH: Controls your adrenal gland hormones, which affect heart rate, blood pressure, and the balance of salt and water in your body

  • Growth hormone: Controls how fast and big your body grows

  • Thyroid-stimulating hormone: Controls your thyroid gland hormones, which control how fast your body's chemical functions work

  • LH and FSH: Control your sex hormones testosterone and estrogen, which affect fertility

  • Prolactin: Controls the production of breast milk

What happens if your pituitary gland doesn't work right?

Your pituitary gland may:

  • Not make enough hormones

  • Make too many hormones

Sometimes there's a problem with only one pituitary hormone. Other times, you have a problem with many or all of the hormones.

If your pituitary gland produces too much, or not enough, of a hormone, you can get health problems such as:

What causes problems with the pituitary gland?

Causes of pituitary gland problems include:

How can doctors tell if I have pituitary gland problems?

Doctors suspect pituitary gland problems from your symptoms. They'll do tests such as:

  • CT scan or MRI of the brain to see if your pituitary gland has grown or shrunk

  • Blood tests measuring hormone levels from the hypothalamus, pituitary, and other glands

How do doctors treat pituitary gland problems?

Treatment depends on the type of problem you have. It may include:

  • Medicine to counteract the effect of too many hormones

  • Surgery to remove a tumor

  • Hormone therapy to replace hormones your body doesn't make enough of

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