Abstract

PIP: 38 patients with dysmenorrhea, aged 21-35 years, were treated with Ponstel (mefenamic acid, a prostaglandin inhibitor). 20 of these subjects were using IUDs (progesterone-releasing). The other 18 women with primary dysmenorrhea were treated during a double-blind study with mefenamic acid or placebo, alternately. Menstrual blood loss (MBL) and amounts of various prostaglandin types (PGE and F) were measured. MBL in IUD users was about 105 ml before treatment. Under mefenamic acid, MBL was reduced to 78 ml. Menorrhagia in these 20 patients was accompanied by severe dysmenorrhea in 12 cases, and the mefenamic acid treatment decreased symptoms in 8 IUD users and eradicated symptoms in the other 4 patients. In the study of primary dysmenorrhea double-blindly, mefenamic acid therapy of 500 mg 3 times daily decreased symptoms distinctly. Average MBL decreased from 57-45 ml. No such changes were found in placebo users. Menstruation was 1 day shorter when mefenamic acid was administered. PGF2 increased in plasma from the day before menstruation onset through cycle Day 2, but this increase was minute under mefenamic acid treatment. 6 patients with primary dysmenorrhea treated with mefenamic acid showed a significant diminution of the PGE1/F2 alpha ratio. Side effects were limited to 3 cases of diarrhea.