Long-term treatment of menorrhagia with mefenamic acid.

Thirty-six women with menorrhagia were treated with mefenamic acid during all menstrual periods for more than 1 year. These women had experienced objective and subjective benefit--menstrual blood loss was reduced and other menstrual symptoms improved during a preliminary 4-cycle double-blind placebo-controlled trial with mefenamic acid (placebo cycles: 65.6 +/- 5.3 ml; mefenamic acid cycles: 45.3 +/- 5.1 ml, mean +/- SEM). This reduction in menstrual blood loss was maintained at 6 to 9 months (49.2 +/- 9.9 ml) and at 12 to 15 months (42.8 +/- 4.8 ml) after the trial. These reductions were significant at the 6- to 9-month (paired t test = 2.18; P less than .05) and the 12- to 15-month interval (paired t test =- 4.40; P less than .001). Significant sustained reductions in blood loss were seen in the women with menorrhagia due to ovulatory dysfunctional bleeding and in those who had undergone tubal sterilization. Significant reductions were also seen in dysmenorrhea, headache, nausea, diarrhea, depression, number of sanitary towels used, and number of mefenamic acid capsules taken. A significant increase in serum ferritin was found between admission and completion of the follow-up trial in 11 women (P less than .01).