Published on Mar, 2022

Last reviewed on Sep, 2023
Authored by Pfizer Medical Team

Hyperprolactinaemia can have some uncomfortable symptoms, including milky discharge from your breasts , in either men or women, or it may be impacting your chance of having a baby.^1,6,7

In this article you’ll learn more about what hyperprolactinaemia is, the symptoms, possible causes and how your doctor will diagnose this condition. In most instances this condition is not life-threatening and can be treated, with people’s symptoms going away within a few weeks of therapy.

What is Prolactin?

Prolactin is a hormone made by the pituitary gland. Its main role is telling the body when to start to make breast milk during pregnancy and breastfeeding.^1,2 It also is involved in male and female reproductive health.^{​7
​​​}Prolactin levels are usually low in men and women who are not pregnant.^{3​​​​​}

What is Hyperprolactinaemia?

Hyperprolactinemia is a condition where there are high levels of prolactin in the blood.²

When prolactin levels are high this can have an impact on other sex hormones that may make it difficult to have a baby (infertility).^1,4,5

What Are The Symptoms Of Hyperprolactinaemia? ^6,7

The symptoms below sometimes occur if you have a prolactinoma, which is a tumour that is usually noncancerous. Prolactinomas vary is size and when they are large they may cause pressure on nerves or parts of the brain.

If this does occur, then these other symptoms may be experienced:^1,7

Some people with hyperprolactinaemia might have no symptoms.⁶

How Often Do These Symptoms Occur with People Who Have Hyperprolactinaemia?

Graph: Rate of symptoms in Women and Men with hyperoprolactinaemia.⁸

How Common Is Hyperprolactinaemia?

Or in every group of 1000 people, 4 may have hyperprolactinaemia.²

Remember, not all people who have hyperprolactinaemia have symptoms and it may go unnoticed. It is usually only when people have symptoms that you may need to look into what is causing the high prolactin levels and potentially need treatment.⁷

What Causes High Prolactin? ⁶

Prolactin levels can rise with some normal bodily functions, such as pregnancy, breastfeeding or stress. These are usually temporary.

Some medications can cause an increase in prolactin.⁶ 
These may include, among others:

• Some antipsychotics (medications for psychosis)

• Some medications for nausea

• Some medications for depression (those in the class called Selective Serotonin Reuptake Inhibitors)

There are medical conditions that cause hyperprolactinaemia. More commonly, these are caused by prolactinomas.

Prolactinomas are tumours caused by the cells in the pituitary gland.
In most cases these tumours are not cancer (benign).⁷

Prolactinomas are classed into two groups based on their size: ^2,7

How Is Hyperprolactinaemia Diagnosed?

Initially your doctor will arrange for you to do a blood test. They will look at the levels of prolactin in your blood.

It is recommended that you have your blood test taken a few hours after waking up and when you’ve been sitting quietly for a short time. This is because prolactin levels can change over the day and rise with levels of stress.^2,3

However always follow the instructions provided by your doctor as they may have reasons for doing the blood test at other times.³

If your prolactin levels are high, you may need further tests to work out exactly what is causing this. This might include a magnetic resonance imaging (MRI) scan.⁶

If it is likely that your medication may be the cause, your doctor may stop you having the medicine for a few days (72 hours) and see if your prolactin level goes back to normal after that time.⁶

Find out what happens next if you are diagnosed with hyperprolactinaemia here.