Hyperprolactinemia

Prolactinomas are the most common pituitary tumors. Hyperprolactinemia is c haracterized by increased production of prolactin, often leading to reprodu ctive dysfunction and galactorrhea. Prolactinomas may also cause male-facto r infertility by producing hypogonadism. In addition, if large, they can pr oduce neurologic symptoms by mass effect in the sellar area. The diagnostic evaluation first requires exclusion of other causes of hyper prolactinemia, such as pregnancy, primary hypothyroidism, numerous medicati ons, and miscellaneous causes. The second step in the diagnostic evaluation is to perform a head scan, preferably an MRT. This is essential in order t o exclude a "pseudoprolactinoma" which would require surgery. Following dia gnostic evaluation, the next step is to determine whether a patient with hy perprolactinemia has an indication for therapy, such as a macroprolactinoma (tumor > 1 cm), hypogonadism (risk of osteoporosis), infertility, signific ant galactorrhea, acne, hirsutism, or headache. The treatment of choice for nearly all patients with hyperprolactinemic dis orders is medical. In most cases, dopamine agonists (bromocriptine, pergoli de, cabergoline) are extremely effective in lowering serum prolactin, resto ring gonadal function, decreasing tumor size, and improving visual fields. The main limitation is side effects, particuarly nausea or orthostatic dizz iness. The newest dopamine agonist, cabergoline, can be given just once or twice a week, is more effective in normalizing prolactin and restoring mens es than bromocriptine, and is significantly better tolerated. However, it i s not yet recommended as first-line therapy for patients seeking fertility, because adequate safety data in pregnancy are not available. For the infre quent patient unable to tolerate, or resistant to, medical therapy, neurosu rgical transsphenoidal resection may be necessary, particularly if the pati ent has a large lesion jeopardizing the optic chiasm. Hyperprolactinemia is a rewarding disorder to manage because patients typically respond well to medication, with restoration of menses and fertility.