Metergoline in the management of hyperprolactinemic amenorrhea and anovulation.

84 patients with elevated serum PRL levels, ranging from 25 to 253 ng/ml, were treated with an antiserotonin agent, metergoline, at the dose of 12 mg/day for 90 days. The clinical complaint was of amenorrhea in 70 cases (plus galactorrhea in 44 cases) and of anovulation in 14 cases (plus galactorrhea in 6 cases). Hyperprolactinemia was due to a pituitary adenoma in 18 cases; in 53 cases it was of unknown origin, while in 7 cases it followed treatment with neuroleptics or with oral contraceptives and in 6 cases it followed a puerperium. In patients with amenorrhea, metergoline induced the appearance of menses in 61 cases (94%), and of ovulation in 46 cases (82%). In 13 of the 14 patients with anovulation, ovulation was restored. Galactorrhea disappeared in 40 out of 50 patients. Metergoline normalized serum PRL levels (less than 20 ng/ml) in 46 cases and significantly reduced serum PRL levels in all but 3 of the remaining patients. In spite of suggested nonhormonal contraceptive measures, 14 patients became pregnant; 2 had abortions and the remaining 12 patients completed by vaginal delivery, uneventful pregnancies. These results indicate metergoline as a safe and effective drug in the management of hyperprolactinemic amenorrhea and anovulation. 49 patients were followed for 2 additional months, receiving no treatment (24 cases) or metergoline at a reduced daily dosage (8 mg/day, 25 cases). Within 60 days, 60% of the first group had relapse of the clinical condition and a rebound elevation of serum PRL levels while only 20% of the second group experienced relapse of amenorrhea and rebound elevation of serum PRL levels (p less than 0.01).