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  Background & Objectives: Regarding to high incidence of dysmenorrhea and influence on daily activities and fewer side effects of herbal medicines than chemical drugs, the aim of this study was to compare the effect of mefenamic acid and matricaria chamomilla (MC) on primary dysmenorrhea.

  Methods: This triple-blind randomized clinical trial study was done on 90 female students residents in dormitories of Kashan University of Medical Sciences in 2012. The subjects were categorized into two groups randomly. Mefenamic acid capsules (250 mg, every 8 hours) were given to the first group from 48 hours before menstruation until 24 hours after it. The second group received MC capsules made in Barij Essence Factory of Kashan (250 mg, every 8 hours). Severity of dysmenorrhea was measured by McGill ruler. Finally, the data were analyzed by SPSS. The chi-squire, fisher and paired t-test were used. The p-value of less than 0.05 was considered as statistically significant difference.

  Results: The result of this study indicated that both chamomilla and mefenamic acid can reduce the severity of pain and hemorrhage (p<0.05) but there was no significant difference between two groups (p>0.05).

  Conclusion: This study showed that matricaria chamomilla is effective in decreasing the severity of primary dysmenorrhea and reducing hemorrhage as well as mefenamic acid.

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Background & objectives: Treatment of dysmenorrhea in women is aimed to bring them to their normal condition. In the present study, the effect of mefenamic acid, a non-steroidal anti-inflammatory drug, was compared with that of transdermal glyceryl trinitrate (GTN) as a tocolytic drug in the management of primary dysmenorrhea.
Methods: A total of 160 nulliparous women aged 18-30 years with primary dysmenorrhea were included in this single blind, clinical trial, which was carried out from 2014 to 2015. The patients were randomly divided into two equal groups. At the beginning of menstruation cycle, the patients in group A received 500 mg oral mefenamic acid, followed by 250 mg mefenamic acid every 6 hours. The patients in group B initially were administered 2.5 mg transdermal glyceryl trinitrate 0.2% every 12 hours to the abdominal skin under the umbilical cord. Treatment was continued for up to 48 hours and repeated for three cycles. Pain scores were assessed by Numerical Rating Scale (NRS) every 4 hours. Adverse effects such as headache and gastrointestinal disorders were recorded. The decrease of pain scale was the primary outcome and adverse effects were the secondary outcome.
Results: The mean pain severity score in in the first 24-hours in mefenamic acid group was lower than that of the glyceryl trinitrate group (p=0.01). On the second day, the mean pain severity scores were not significantly different between the two groups. The mean pain severity scores in the second day of second cycle (p<0.001) and in the first day of third cycle (p=0.001) were significantly lower in mefenamic acid group than in glyceryl trinitrate group. The side effects were also higher in the glyceryl trisitrate group than in the mefenamic acid group, but this difference was not statistically significant. The most common complication was headache in the group receiving glyceryl trinitrate (18.75%) and nausea in the group receiving mefenamic acid (26.25%). The satisfaction rate was 42.2% in the patients receiving transdermal glyceryl trinitrate, while it was 78.5% in patients receiving mefenamic acid; therefore, the patients in the mefenamic acid group were more satisfied (p=0.004).
Conclusion: The analgesic effects of oral mefenamic acid were better than transdermal glyceryl trinitrate in the management of primary dysmenorrhea. The adverse effects of these two drugs were not significantly different, but the type of complications was different in both groups.