Bromocriptine and norethisterone in the treatment of premenstrual syndrome.

Thirty-six women suffering from premenstrual syndrome were treated with bromocriptine or norethisterone in a randomized placebo-controlled double-blind study. Bromocriptine decreased breast engorgement and irritability (P less than .01) and also decreased the total score of all symptoms (P less than .05). Weight gain during the luteal phase was smaller (P less than .05) during bromocriptine than during placebo treatment. Norethisterone treatment alleviated (P less than .05) breast tenderness. Changes in hormonal parameters and liver function tests during bromocriptine treatment were minimal, whereas norethisterone decreased serum levels of luteinizing hormone (P less than .01), follicle-stimulating hormone (P less than .001), and progesterone (P less than .05), while increasing the serum level of prolactin (P less than .01) and gamma-glutamyltranspeptidase activity (P less than .05). Serum levels of cholic acid and chenodeoxycholic acid remained unchanged during both therapies. Bromocriptine treatment brought about side effects in 6 and norethisterone in 3 women. At the doses used, bromocriptine appears more efficient than norethisterone with regard to premenstrual symptoms, although norethisterone is better tolerated.