Prolactin is a hormone produced from the pituitary gland. It helps stimulate and maintain breast milk production. Hyperprolactinemia describes an excess of this hormone in a person’s body.

It’s normal to have this condition during pregnancy or when producing milk for breastfeeding.

Certain conditions or use of specific medications, however, can cause hyperprolactinemia in anyone. The causes and effects of high prolactin levels vary depending on a person’s sex.

Read on to learn about the causes, symptoms, and treatment of hyperprolactinemia.

An increased level of prolactin may be caused by a variety of secondary conditions. Most often, hyperprolactinemia is caused by pregnancy — which is normal.

According to a 2013 study , pituitary tumors may be the cause of almost 50 percent of hyperprolactinemia. A prolactinoma is a tumor that forms in the pituitary gland. These tumors are typically noncancerous. But they can cause symptoms that are different for depending on a person’s sex.

Other causes of hyperprolactinemia include:

Symptoms of hyperprolactinemia can differ in men and women.

Since prolactin levels affect milk production and menstrual cycles, it can be difficult to detect in men. If a man is experiencing erectile dysfunction, their doctor may recommend a blood test to look for excess prolactin.

Symptoms in females:

Symptoms in males:

To diagnose hyperprolactinemia, a doctor performs a blood test to check prolactin levels.

If prolactin levels are high, the doctor will test for other conditions. If they suspect a tumor, they may order an MRI scan to try to determine if a pituitary tumor is present.

Treatment of hyperprolactinemia is mostly focused on returning prolactin levels to normal. In the case of a tumor, surgery may be needed to remove the prolactinoma, but the condition can often be managed with medication.

Treatment may involve:

Typically, hyperprolactinemia is treatable. Treatment will depend on what’s causing excess prolactin secretion. If you have a tumor, you may need surgery to remove the tumor and return your pituitary gland to normal.

If you’re experiencing irregular lactation, erectile dysfunction, or loss of sexual desire, notify your doctor of your symptoms so they can perform the necessary tests to determine the cause.