What Is Hyperprolactinemia?

Medically Reviewed by Melinda Ratini, MS, DO on February 29, 2024
3 min read

Hyperprolactinemia is a medical condition in which excess prolactin is produced. Prolactin is a hormone involved in the production of milk in a woman's breast. Research has also shown that prolactin is essential in different aspects of reproduction. 

Prolactin affects the sex hormone levels in both men and women. The pituitary gland, which is a pea-sized organ at the base of the brain, produces and releases prolactin. An excess of prolactin in the blood could be due to physiological (changes in the body), pathological (due to another disease), or idiopathic (no cause known) abnormalities. 

Hyperprolactinemia has several causes, including tumors, certain prescription medications, and other health conditions.  

Tumors. A prolactinoma is a tumor or cancerous growth on the pituitary gland. It is the most common cause of this disease. The tumor produces excess prolactin. Depending on your individual condition, the tumor may be small or large. 

Most often, these tumors are benign and do not cause cancer. Tumors smaller than a centimeter are called microprolactinomas. Larger tumors are called macroprolactinomas. Larger tumors lead to other issues, like vision problems and headaches. 

Medicine. Besides tumors, some prescription medications can also increase the levels of prolactin in the body. These medications are prescribed for: 

  • High blood pressure 
  • Birth control 
  • Menopausal symptoms 
  • Pain 
  • Nausea and vomiting 
  • Heartburn 
  • Depression 

If you are using medicines for any of the diseases mentioned above and develop hyperprolactinemia, speak to your doctor. They will prescribe different medications or offer appropriate guidance.  

Other conditions. You may also develop hyperprolactinemia if you have one of the following conditions. 

  • Hypothyroidism, a condition in which the thyroid does not produce the required amount of thyroid hormones 
  • Pregnancy 
  • Injury to the chest wall 
  • Shingles, or other conditions that impact the chest wall 
  • Other tumors that affect the pituitary gland 
  • Chronic kidney or liver conditions 

During diagnosis, your doctor will also check for the symptoms of these conditions. Sometimes, hyperprolactinemia is idiopathic, which means there is no known cause for it. 

Prolactinomas affect women more commonly than men. 

Common symptoms are bone loss, decreased sex drive, and infertility. Additionally, women may experience the following symptoms: 

  • Vaginal dryness that results in pain during sex 
  • Menstrual problems, such as irregular or no periods 
  • Breast milk production even when not nursing or pregnant 

Meanwhile, men may have the following symptoms: 

  • Erectile dysfunction, which is an inability to keep or get an erection 
  • An increase in breast size (gynecomastia)
  • Decrease in body hair and muscle mass 

High levels of prolactin in the blood are detected using a blood test. If your doctor finds high prolactin levels, they will prescribe more tests to check thyroid hormone concentration in the blood.

Your doctor will also ask you about the medicines you are using and whether you are pregnant. If they think you may have a prolactinoma, they will recommend performing an MRI. This imaging test shows an image of the body tissues and helps doctors see if a tumor is growing in your body. 

The treatment for hyperprolactinemia depends on the cause. Some people have high prolactin levels but do not show any symptoms of the condition. They do not need treatment. Options for people who have tumors are: 

  • Prescription medicines. Your doctor will prescribe prescription medicines that lower the level of prolactin in the blood. Most medications work well for people and are tolerated by the body. 
  • Surgery. If medicines are not helping, your doctor may recommend surgery to remove the tumor. 
  • Radiation. If both surgery and medicines are not working, radiation is used. It shrinks the tumor. 

If you have developed hyperprolactinemia due to a tumor, you may experience the following complications: 

  • Bone loss. An excess of prolactin in the blood can lower the production of sex hormones, such as testosterone and estrogen. A lower level of these hormones results in decreased bone density. 
  • Vision loss. If the prolactinoma is not treated in time, it can grow and cause vision loss. 
  • Pregnancy complications. If prolactinoma develops during pregnancy, it can cause vision changes and headaches, among other complications. 

Speak to your doctor right away if you notice any signs of the condition, especially if you are already pregnant or are trying to conceive.