Prolactinoma medical therapy

Overview
The goal of treatment is to return prolactin secretion to normal, reduce tumor size, correct any visual abnormalities, and restore normal pituitary function. As mentioned above, the impact of stress should be ruled out before the diagnosis of prolactinoma is given. Exercise can significantly reduce stress and, thereby, prolactin levels. It should also be noted that higher prolactin levels may contribute to the development of prolactinomas so the diagnosis can be self-fulfilling if the original cause is stress. In the case of very large tumors, only partial reduction of the prolactin levels may be possible.

Medical therapy
Dopamine is the chemical that normally inhibits prolactin secretion, so doctors may treat prolactinoma with bromocriptine or cabergoline, drugs that act like dopamine. This type of drug is called a dopamine agonist. These drugs shrink the tumor and return prolactin levels to normal in approximately 80% of patients. Both have been approved by the Food and Drug Administration for the treatment of hyperprolactinemia. Bromocriptine is the only dopamine agonist approved for the treatment of infertility. Another dopamine agonist, pergolide, is available in the U. S., but is not approved for treating conditions that cause high blood levels of prolactin.

Bromocriptine is associated with side effects such as nausea and dizziness. To avoid these side effects, it is important for bromocriptine treatment to start slowly.

Bromocriptine treatment should not be interrupted without consulting a qualified endocrinologist. Prolactin levels often rise again in most people when the drug is discontinued. In some, however, prolactin levels remain normal, so the doctor may suggest reducing or discontinuing treatment every two years on a trial basis.

Cabergoline is also associated with side effects such as nausea and dizziness, but these may be less common and less severe than with bromocriptine. As with bromocriptine therapy, side effects may be avoided if treatment is started slowly. If a patient's prolactin level remains normal for 6 months, a doctor may consider stopping treatment. Cabergoline should not be interrupted without consulting a qualified endocrinologist.