Effect of bromocriptine on the premenstrual syndrome. A double-blind clinical trial.

Twenty-one patients suffering from the premenstrual syndrome were each studied during three menstrual cycles. After a control cycle, bromocriptine and placebo were given during the luteal phase of the cycle in a random double-blind cross-over manner, each patient serving as her own control. The dosage of bromocriptine was 2-5 mg twice daily. Serum prolactin levels were found to equal during the follicular and luteal phases, except when reduced by bromocriptine. Serum progesterone and oestradiol-17-beta were within normal ranges, and did not change during treatment. Medication considerably improved all the premenstrual symptoms, but mastodynia was the only one where bromocriptine was significantly better than the placebo.