What do my high prolactin levels mean?

Dr. Jack Merendino, MD
Endocrinology Diabetes & Metabolism
Prolactin is a hormone made by the pituitary gland. Its primary purpose is to promote milk production for a woman who is breastfeeding. In other situations an elevated prolactin level is abnormal and may cause problems.

There are several symptoms or problems that can result from high prolactin levels. Breast enlargement or tenderness in men (called gynecomastia), or breast milk production in both men and women can occur. A high prolactin level sometimes causes infertility in a woman, or erectile dysfunction, a low testosterone level or a low sperm count in a man. If someone sees a doctor for any of these conditions, a prolactin level should be measured.

A high prolactin level may result from a pituitary tumor which is releasing too much prolactin. Pituitary tumors are actually fairly common. They are rarely cancerous, but they can cause problems either by over-producing a hormone such as prolactin, or by growing in size and pressing on surrounding structures. If a person has symptoms that lead to a diagnosis of an elevated prolactin level, an MRI of the pituitary gland is usually performed unless there is another obvious cause, such as a medication for the elevated prolactin. At other times, a person has a CT scan or MRI scan of the brain for unrelated reasons and a pituitary tumor is identified when it was not suspected. In this case a prolactin level, as well as measurement of other pituitary hormones, is usually done, even if there seem to be no symptoms. When a person has a prolactin-secreting pituitary tumor the prolactin level is usually fairly high.

Many times a person with a slightly elevated prolactin does not have a pituitary tumor on MRI scan. In this case, the tumor may be too small to be seen, or normal-appearing pituitary tissue may just be making too much prolactin. Some medications, especially those used to treat psychotic disorders such as schizophrenia, will cause the prolactin level to rise.

If the prolactin level is just a little elevated, there is no tumor and there are no symptoms, treatment may not be necessary. If a drug causing a prolactin elevation can safely be stopped, the prolactin level will fall. If there is a large pituitary tumor, or a high level causing problems, a person can be treated with bromocriptine (Parlodel) or cabergoline (Dostinex) which will usually lower the prolactin level, shrink the tumor if there is one, and lead to improvement in symptoms.

Continue Learning about Prolactinoma


Found on the pituitary gland, prolactinoma is a non-cancerous tumor that causes the body to overproduce the hormone prolactin which stimulates breast milk. It decreases levels of estrogen for women and testosterone for men. Prolac...

tinoma is not life-threatening but, if left untreated, it can cause infertility and impaired vision. It is the most common type of tumor found in the pituitary gland. Symptoms include unexplained breast milk in women who are not pregnant or nursing, changes in menstruation and decreased sexual interest. The symptoms are less obvious in men which can often delay a visit to the doctor. Men experiencing erectile dysfunction, headaches and problems with their vision should make appointment with their doctor. Doctors use drug therapy to effectively restore prolactin levels in the body. Surgery and radiation may also be used to remove the tumor.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.