The goal of treatment is to return prolactin secretion to normal, reduce tumor size, correct any visual abnormalities and restore normal pituitary function. In the case of very large tumors, only partial achievement of this goal may be possible. Because dopamine is the chemical that normally inhibits prolactin secretion, doctors first treat a prolactinoma with dopamine agents (agonists).
Bromocriptine shrinks the tumor and returns prolactin levels to normal in the majority of patients. To avoid side effects such as nausea and dizziness, it is important for bromocriptine treatment to start slowly. Usual maintenance doses are 2.5 (one tablet) to 7.5 mg (3 tablets) daily.
Bromocriptine treatment should not be interrupted without consulting an endocrinologist. Prolactin levels often rise again in most people when the drug is discontinued.
Another dopamine agonist is cabergoline, which may be more effective and better tolerated than bromocriptine. Another advantage of cabergoline is that it may be prescribed as a weekly dosage of 0.5 (one tablet) to 2.0 (4 tablets) mg weekly.