Symptoms of high prolactin in females: what to look out for

Irregular periods, unexpected nipple discharge, low libido, or trouble getting pregnant can be confusing, especially when there is no obvious cause. In some cases, these symptoms may be linked to high prolactin, a hormone best known for its role in pregnancy and breastfeeding. While prolactin naturally rises during these times, higher-than-expected levels outside pregnancy or breastfeeding can affect your cycle, fertility, and overall wellbeing. Understanding the signs of high prolactin can help you know when to test, when to seek medical advice, and what steps to take next.

Table of Contents

• What is high prolactin?

• Recognising high prolactin symptoms

• Causes of high prolactin levels

• What to do if you suspect high prolactin

• Frequently asked questions about high prolactin

What is high prolactin?

Prolactin, also called PRL or lactotropin, is a hormone. Besides hundreds of bodily functions, it:

• signals breast tissue to grow during pregnancy

• supports milk production for breastfeeding after birth

Prolactin is present in everyone, including men and women who are not pregnant or breastfeeding.

Prolactin levels naturally rise during pregnancy and after childbirth, especially while breastfeeding. Outside of these situations, higher-than-expected prolactin levels are known as hyperprolactinaemia, which can have several possible underlying causes.

Source: National Library of Medicine, 2024; Cleveland Clinic, 2024; Cleveland Clinic, 2024 

Recognising high prolactin symptoms

Symptoms of high prolactin levels can be mild, and some people may have no symptoms at all.

Symptoms in anyone can include:

• Infertility

• Low libido

• Low bone mass, also known as osteopenia

• Milky nipple discharge when not pregnant or breastfeeding

• If high prolactin is caused by a prolactinoma, other symptoms may also occur, such as headaches, vision changes, or low levels of other pituitary hormones

Symptoms in women can include:

• Irregular or missed periods not related to menopause

• Pain during penetrative sex due to vaginal dryness

Symptoms in men can include:

• Erectile dysfunction

• Low testosterone levels

• Enlarged breast tissue, also known as gynaecomastia

Source: Cleveland Clinic, 2024; Mayo Clinic, 2025 

Causes of high prolactin levels

There are several possible causes of high prolactin levels. Some are temporary and harmless, while others may need medical follow-up.

1. Prolactinoma
   A benign pituitary gland tumour that produces too much prolactin. This is the most common cause of high prolactin levels.

2. Other pituitary gland problems
   Tumours near the pituitary gland, or radiation therapy in this area, may result in high prolactin.

3. Certain medications
   Some medicines can raise prolactin. These may include certain antidepressants, antipsychotics, blood pressure medications, birth control pills, oestrogen therapy, anti-nausea medicines, heartburn medicines, and opioid painkillers.

4. Underlying health conditions
   Conditions such as an underactive thyroid, chronic kidney or liver disease, Cushing disease, chest wall injury, shingles on the chest, or polycystic ovary syndrome may contribute to high prolactin levels.

5. Unknown cause
   Sometimes no clear cause is found. This is called idiopathic hyperprolactinaemia and may resolve on its own over time.

Source: Cleveland Clinic, 2024; National Libary of Medicine, 2024

Speak with your healthcare provider if you have any concerns, or if you need an accurate diagnosis and appropriate treatment.

What to do if you suspect high prolactin

If you think you may have symptoms of high prolactin, start by paying attention to patterns. Keep a simple record of your symptoms and any lifestyle changes. This information can be very useful when speaking with a healthcare professional.

You may also consider taking an at-home prolactin test, such as the Homed-IQ Hormone Test for Women. You can order the test online, collect your sample at home, and send it by post to an ISO-certified laboratory. Once your sample has been analysed, you receive clear results online.

However, testing should not replace medical advice. If your prolactin level is high, or your symptoms continue despite a normal result, speak with your GP. They can assess your symptoms, recommend any further tests if needed, and help determine the most appropriate treatment.

Frequently asked questions about high prolactin

When are prolactin levels considered high?

Normal prolactin levels can vary slightly between laboratories, so it is important to check the reference range provided on your lab report. In general, prolactin levels are usually less than 20 ng/mL in males and less than 25 ng/mL in females who are not pregnant or breastfeeding. During pregnancy and breastfeeding, prolactin levels are naturally much higher, typically ranging from 80 to 400 ng/mL. If you are unsure what your result means, speak with your healthcare provider for guidance (Cleveland Clinic, 2024).

How is high prolactin diagnosed at home?

High prolactin is diagnosed with a blood test that measures prolactin in your blood. With the Homed-IQ Hormone Test for Women, you collect a finger-prick blood sample at home and send it to a certified laboratory for analysis. The test measures prolactin alongside other key hormones, including testosterone, TSH, LH, FSH, and estradiol, helping you get a broader picture of your hormone health. If your prolactin result is raised, discuss it with your GP, who can advise whether further testing or treatment is needed.

How is high prolactin treated?

Treatment for high prolactin depends on the underlying cause and whether symptoms are present. Some people with mild or no symptoms may not need treatment. If a prolactinoma, a noncancerous tumour, is the cause, medication is usually the first treatment option. Surgery or radiation therapy may be considered if medication is not effective. If high prolactin is linked to another medication, a healthcare provider may recommend switching to an alternative (Cleveland Clinic, 2024).