A double-blind cross over study comparing Achillea wilhelmsii with mefenamic acid for the treatment of primary dysmenorrhea

Abstract

A. wilhelmsii is used to regulate the menstrual cycle and reduces bleeding and pain in folk medicine [1]. We compared the effect of the powder of flowering aerial parts of A. wilhelmsii with mefenamic acid on primary dysmenorrheal pain. Randomized, double-blind and crossover trial was conducted in seventy single and sexually inactive female students (aged 26±2) who had primary dysmenorrhea, regular menstrual cycles, and pain score of 5 or higher on Visual Analog Scale. The study was conducted over 3 menstrual cycles as follows: at cycle 1 (placebo) pain severity was measured in first day of menstruation; at cycle 2, the volunteers were randomly assigned to take A. wilhelmsii (1000mg) or mefenamic acid (250mg) at recommended doses as needed; at cycle 3, the volunteers switched treatments. The pain intensity was recorded at regular scheduled intervals (1, 2, 3 and 6h) after taking the medications. Compared with placebo both mefenamic and A. wilhelmsii decreased the pain score significantly (p<0.001). But the pain relief induced by A. wilhelmsii was high (p<0.01). The menstrual blood loss (p=0.02), signs of dysmenorrhea (p=0.001), the duration of bleeding and pain (p=0.001) in A. wilhelmsii treated group were less than of mefenamic acid. The duration of self-medication for mefenamic acid was 167±108min and for A. wilhelmsii 99±82 (p<0.0001). The number of capsules chosen by patients was 1.7±0.8 and 2.1±0.7 (p<0.0001) for the plant and mefenamic acid, respectively. A. wilhelmsii, when taken in recommended doses, was more effective in alleviating pain and bleeding associated with primary dysmenorrhea than mefenamic acid.