A prolactinoma is a noncancerous growth that develops on the pituitary gland, a small, bean-shaped gland located at the base of the brain. This type of tumor causes the pituitary gland to produce an excessive amount of prolactin, a hormone primarily involved in milk production. While a prolactinoma can lead to a range of symptoms, headaches are a common manifestation that can significantly impact daily life.
Characteristics of a Prolactinoma Headache
Prolactinoma headaches have distinctive features, unlike typical tension or migraine headaches. The pain is frequently described as a constant pressure, sometimes feeling like a balloon inflating inside the skull. This sensation can be located behind the eyes, in the forehead, or spread diffusely across the head. Headaches can be unilateral or bilateral.
Pain quality varies from a dull ache to sharp, severe throbbing. These headaches are often persistent, occurring daily or with high frequency. Their severity is not always directly related to the tumor’s size; even smaller tumors can sometimes cause significant pain.
The underlying mechanism of prolactinoma headaches is distinctive. They result from the tumor pressing on surrounding brain structures, such as the optic nerves or the dura mater, rather than a direct effect of elevated prolactin levels. This mechanical pressure can lead to pain that may not respond effectively to common over-the-counter pain relievers. In rare instances, a sudden, severe headache, often described as the “worst headache of one’s life,” can indicate pituitary apoplexy, a medical emergency involving bleeding into the tumor.
Other Symptoms of Prolactinoma
Beyond headaches, prolactinomas cause other symptoms due to tumor pressure and excess prolactin. Visual disturbances occur when a larger tumor presses on the optic chiasm, where the optic nerves cross. This pressure can lead to blurred vision, double vision, or a loss of peripheral vision, often described as bitemporal hemianopsia, where vision is lost in the outer halves of both visual fields.
Elevated prolactin levels cause specific hormonal imbalances. In women, common symptoms include irregular or absent menstrual periods, which can be an early indicator. Milky breast discharge unrelated to childbirth or nursing, known as galactorrhea, is frequent. Women may also experience reduced libido, vaginal dryness, and infertility.
Men with prolactinomas may experience reduced libido, erectile dysfunction, and infertility, often due to decreased testosterone levels. Breast enlargement, or gynecomastia, and a decrease in facial or body hair can also occur. Both sexes may experience general symptoms like fatigue, mood changes, and bone loss due to hormonal disruptions.
When to Consult a Doctor
Seek medical evaluation for persistent or worsening headaches, especially with other concerning symptoms. Prompt medical attention is warranted if headaches are coupled with vision changes (e.g., blurred vision, peripheral sight loss) or unexplained milky nipple discharge. Menstrual irregularities in women or reduced libido and erectile dysfunction in men are also significant indicators.
An early diagnosis allows for timely management of the condition. A healthcare provider may conduct a physical examination, inquire about your symptoms, and order specific tests. These include blood tests to measure prolactin levels and imaging studies, such as an MRI of the pituitary gland, to visualize the tumor.