Tolfenamic acid and mefenamic acid in the treatment of primary dysmenorrhoea

The clinical efficacy of tolfenamic acid and mefenamic acid in the treatment of primary dysmenorrhoea was studied in a prospective, controlled, double-blind, cross-over study comprising 73 patients aged 13-39 with an average body weight of 56 kilos. The patients were randomized to receive either tolfenamic acid (200 mg t.i.d.) or mefenamic acid (500 mg t.i.d.) for 3 days, during 3 consecutive menstrual cycles each, in a sequential design A-B or B-A. At the beginning and at the end of each treatment period, 13 dysmenorrhoeic symptoms were evaluated on a visual analogue scale (lower back pain, interference with daily activities, nausea, vomiting, diarrhoea, headache, dizziness, fatigue, sweating, chills, hot flashes, depressant states, and mood swings). The data were analyzed by using two statistical models. The first one, for the 73 patients, by making paired comparisons regardless of treatment sequence. With respect to the initial values, the results showed that both drugs were statistically significant (P < 0.05) in reducing the intensity of the evaluated symptoms. When comparing both treatments, tolfenamic acid showed a significant difference as to interference with daily activities (P < 0.025) and hot flashes (P < 0.005). In the result analysis with the second model, the groups were divided according to the first assigned treatment and paired comparisons were made. It was observed that the group receiving tolfenamic acid in the last sequence reached a higher level of response and statistical significance was demonstrated in 8 of 13 evaluated symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)