Objective: To assess the efficacy and tolerability of monthly injections of the long-acting repeatable bromocriptine in patients with macroprolactinomas.
Design: Open and prospective trial.
Setting: This multicenter trial was carried out in seven university hospitals.
Patients: Forty-two patients with prolactin (PRL)-secreting macroadenomas.
Interventions: Fifty to 200 mg of the drug were administered intragluteally every 28 days for 6 to 24 months.
Main outcome measures: The efficacy was assessed by repetitive plasma PRL measurements, visual field determinations, and computed tomography scan examinations.
Results: After the first 50-mg injection, the mean percentage decrease of PRL levels was 71% from baseline on day 14; between days 1 and 28, PRL levels were suppressed to normal in nine cases, and a clear tumor shrinkage was documented in 21% of the patients. Normalization of PRL secretion was obtained in 62%, and a clear-cut reduction in tumor size in 50% of the patients after 6 months of treatment.
Conclusions: The long-acting repeatable form of bromocriptine was a well tolerated and quickly effective treatment in most of these patients with macroprolactinomas.