Clinical and Hormonal Response To Bromocriptin (CB-154) in the Galactorrhea Syndromes

Nine female patients with galactorrhea were selected for treatment with Bromocriptin® (CB-154), a specific inhibitor of prolactin secretion. Elevated plasma prolactin (hPRL) was found in 7 of these cases, whereas 2 exhibited values within normal limits. LHRH (100 μg) stimulation elicited plasma LH/FSH increases in 6 of the women who were amenorrheic prior to therapy, indicating a suprasellar cause for the patients' failure to cycle. After TRH (250 μg) stimulation, 5 women out of 6 exhibited a blunted hPRL response and 4 of them failed to show any elevations after administration of chlorpromazine. It was only in one patient who exhibited basal hPRL within the normal range, that an average response to TRH was elicited. The possible mechanisms explaining the low levels of pituitary stimulation obtained are discussed. Treatment with CB-154 (3–5 mg/day) induced a fall in serum hPRL accompanied by cessation of milk secretion in 8 patients. Menses were restored in 7 amenorrheic women and corpora lutea formation was confirmed by elevated plasma progesterone levels in 6 of them. One patient exhibiting normal serum hPRL and amenorrhea following the discontinuation of an oral contraceptive failed to resume menses under CB-154 therapy despite a fall in hPRL, suggesting that the mechanisms involved were not prolactin-dependent. Hyperprolactinemia and galactorrhea tended to recur when therapy was withheld, indicating to a certain extent persistent autonomy of the mechanisms involved. Since CB-154 has been found to inhibit not only prolactin secretion but also hormone synthesis, it remains to be seen whether long-term therapy with this agent may induce permanent remissions in patients with galactorrhea-amenorrhea.