Elevated levels of prolactin are easy to detect with a simple blood test, but finding the cause of the excess hormone can be a bit more difficult.
Dopamine-suppressing drugs may cause prolactin levels to rise, since dopamine plays a role in managing prolactin levels. Patients who take certain prescription medications (including some anti-psychotic, anti-nausea, or blood pressure medications) may experience the symptoms of elevated prolactin levels due to the decrease in prolactin-suppressing dopamine.
Non-prolactinoma pituitary tumors may also cause elevated levels of prolactin. The interplay between hormones is extremely complex, and a disturbance in any one hormone level can upset the balance of the others.
Thyroid and adrenal conditions may affect prolactin levels — individuals with hypothyroidism (underactive thyroid), adrenal insufficiency may experience increased levels of prolactin.
Macroprolactin – a nonfunctioning prolactin molecule that is being counted by the lab assay but has no biological activity and doesn’t require treatment.
Breast pathology or stimulation need to be excluded.
Still, the most common cause of elevated prolactin is a prolactinoma. If blood tests reveal elevated levels of prolactin and the other causes are excluded, the patient should be referred for imaging tests to look for a tumor.
Magnetic resonance imaging (MRI) produces detailed images of the brain and allows doctors to detect the presence of a tumor. The test is noninvasive, but it requires time in a scanner to produce tiny slices of images that are then combined into three-dimensional pictures. Sometimes the patient will need a special contrast agent in advance to increase the visibility of any abnormality found.
Prolactinoma may be treated medically with prolactin-suppressing drugs; it can also be treated with radiation in the rare instances a tumor is locally aggressive.
A prolactinoma may be removed surgically if medication cannot control the prolactin production or tumor size and the patient cannot tolerate the medication. (See Surgery for a Pituitary Tumor.) Pituitary tumors are complex lesions that should be treated at major medical centers, by a team experienced in the diagnosis and treatment of tumors affecting the hormones.
The Weill Cornell Medicine Brain and Spine Center is fortunate to be home to an internationally recognized surgical team with advanced skills in minimally invasive procedures to remove pituitary tumors. Neurosurgeon Theodore Schwartz, MD, routinely uses endonasal (through the nose) approaches to removing pituitary tumors, with no head or facial scarring. (See video of endonasal surgery technique.) Dr. Schwartz is also pioneering new transorbital and supraorbital approaches. The team has operated successfully on tumors that other surgeons have deemed impossible to remove. (See video of patient who had a giant tumor removed endonasally.) Dr. Dobri is well versed in all available medications for prolactinoma and has taken care of many patients with complex disease that requires combination medical therapy.
Reviewed by: Georgiana Dobri, M.D.
Last reviewed/last updated: September 2023