Efficacy and tolerability of a long-acting intramuscularly injectable depot preparation of bromocriptine: the results of a double blind study

The tolerability and efficacy of a long-acting im applicable form of bromocriptine (Parlodel LAR®) was tested in a double-blind approach in 20 patients with hyperprolactinemia or prolactinoma, 17 of them complaining of persistent side effects on oral treatment with dopamine agonists. The study-code revealed similar characteristics for age, sex, weight, clinical symptoms and previous therapy in both groups but prolactin serum levels were higher in the verum group even though the difference was not significant. In all 10 patients receiving Parlodel LAR® prolactin serum concentrations were significantly suppressed and tumor size was reduced in 5 of the 9 patients with visible tumors when controlled after 28 days. In contrast, no significant change in serum prolactin levels was observed in the placebo group and tumor size of all visible tumors was not altered. Side effects typically reported for dopamine agonists started 3 h after application in the verum group and were significantly different to the unspecific side effects reported in the placebo group during the first 72 h. Thereafter systemic tolerability was indistinguishable between both groups. The local tolerability at the injection site was excellent for both, Parlodel LAR® and placebo.