Use of cabergoline in the long-term treatment of hyperprolactinemic and acromegalic patients.

Cabergoline (Cab), a very potent and long-lasting dopaminergic compound, was administered to 26 women with pituitary microprolactinoma [mean serum PRL levels: 124.8 +/- 11.3 micrograms/l (+/- SE), range 62-300 micrograms/l] and 3 patients with GH-secreting pituitary adenoma (2 with associated PRL hypersecretion) for 12 and 24 months, respectively. In microprolactinomas, a stable normoprolactinemia was achieved in 96.1% of cases: in 13 women (50%) with the lowest dose of the drug (0.5 mg/week), and in other 12 patients (46.1%) with increasing doses up to 3 mg/week. All the oligomenorrheic/amenorrheic women, except one, restored regular and ovulatory menses. Two patients became pregnant. Pituitary abnormalities at high resolution-CT (HR-CT) scan disappeared in 13 of 19 patients (68.4%) after 12 months of therapy and this feature persisted in 8/13 cases (61.5%) 12 months after drug withdrawal. During Cab discontinuation (range: 3-60 months), mean serum PRL levels remained significantly lower than the basal ones. Six of 25 women are still without therapy. In 2 patients, normoprolactinemia persisted up to 38 and 60 months, respectively. Cab treatment was re-instituted in 13 patients because of the recurrence of hyperprolactinemia. Five patients were lost at follow up. In all the acromegalic patients, Cab (1-3 mg/week) normalized serum GH, IGF-I and PRL levels. A clear improvement in clinical symptoms was observed in all patients, but neuroradiological improvement in only one. Cab therapy was very well tolerated, as only seven patients complained of mild and transient side-effects and none had to stop treatment. In conclusion, Cab is an effective, safe, and well tolerated dopaminergic compound for the treatment of hyperprolactinemic disorders and the control of the clinical and hormonal features of dopamine-sensitive acromegalic patients.