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Last full review/revision Feb 2021| Content last modified Feb 2021
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What is galactorrhea?

Galactorrhea is when your breasts make milk when you aren’t breastfeeding a baby. Both men and women can get galactorrhea.

What causes galactorrhea?

Prolactin is a hormone from your pituitary gland Overview of 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... read more that causes your breasts to make milk. Prolactin normally increases in women who have just given birth, so they can breastfeed their baby. Too much prolactin causes your breasts to make milk even when you're not pregnant. Prolactin can even make a man's breasts produce milk.

The most common cause of galactorrhea in men and women is:

  • A tumor on your pituitary gland that causes the gland to make too much prolactin

Other causes of having too much prolactin include:

Having too much prolactin also can affect sexual function and fertility in men and women.

What are the symptoms of galactorrhea?

For women:

  • Your breasts making milk unexpectedly

  • Not having periods, or having fewer periods

  • Vaginal dryness because of low estrogen levels

  • Sometimes, excess body hair (hirsutism)

For men:

In both women and men, a large tumor can press on nerves in the brain and cause headaches or partial blindness.

How can doctors tell if I have galactorrhea?

How do doctors treat galactorrhea?

Doctors treat galactorrhea with:

If your symptoms are mild and don't bother you, doctors may not treat your galactorrhea. You may need to take estrogen for low estrogen levels, and doctors will do follow-up CT scans or MRI each year to make sure your pituitary tumor isn't growing larger.

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