Effectiveness of short-term maintenance treatment with cabergoline in microadenoma-related and idiopathic hyperprolactinemia.

Objective: This study aimed to determine the effectiveness of short-term maintenance treatment with cabergoline and to find out minimum effective dosage of cabergoline during maintenance treatment for patients with microadenoma-related and idiopathic hyperprolactinemia.

Study Design: Cabergoline was administered orally at a dose of 0.5 mg twice per week to 164 de novo hyperprolactinemic patients until serum prolactin level normalized. After this initial treatment phase, patients started on maintenance phase for which they were previously randomized. No maintenance treatment (Group I, n = 36) or cabergoline 0.5 mg (Group II, n = 46), 0.25 mg (Group III, n = 39), 0.125 mg (Group IV, n = 43) was administered twice per week for 8 weeks as maintenance treatment. Then, maintenance phase was finalized and patients were followed up for 6 months. Mean serum prolactin levels through maintenance treatment phase and follow-up period were assessed between groups and within groups.

Results: Except for group I, all the groups showed a similar pattern with fast decrease of serum prolactine level during maintenance phase and slower increase during the follow-up period. Notably, the average prolactin level was significantly lower at the last follow-up visit than at the diagnosis time in all of the groups. Stable normoprolactinemia of the groups at the end of follow-up period were 47.2, 37, 48.7, and 34.9%, respectively.

Conclusions: The results indicate that short maintenance treatment in idiopathic and microadenoma-related hyperprolactinemia seems as effective as long maintenance treatment in the present study. But, further studies with larger study population and longer follow-up period are needed to make a decision about early treatment withdrawal. Also, during the maintenance treatment administration of medicine to patients should be tapered down to the lowest dose that will maintain prolactin levels normal.