The Effects of Lemon balm (Melissa officinalis L.) Alone and in Combination With Nepeta menthoides on the Menstrual Bleeding in Students With Premenstrual Syndrome: A Randomized Controlled Trial

An increased amount of menstrual bleeding in women causes anemia and decreased quality of life. The present study aimed to determine the effects of lemon balm alone and in combination with Nepeta menthoides on menstrual bleeding in students with premenstrual syndrome. This triple-blind randomized controlled trial included 93 female students with aged 18 years and older. The intervention groups received 500 mg capsules of lemon balm alone or lemon balm in combination with N. menthoides. The control group received 500 mg capsules of placebo twice daily in the luteal phase for two consecutive menstrual cycles. A Pictorial Blood Loss Assessment Chart (Higham) was completed at baseline and 1 and 2 months after the intervention. Data were analyzed using the chi-square, one-way analysis of variance (ANOVA), analysis of covariance (ANCOVA), and repeated measures tests. The differences in baseline characteristics and Higham scores of the three groups were not statistically significant (P > 0.05). General linear model analysis with adjustment for the preintervention menstrual bleeding level showed that there was no statistically significant difference in terms of menstrual bleeding mean in the first (P = 0.602) and second menstrual periods after intervention (P = 0.148) among the three intervention groups. Based on the results of this study, treatment with lemon balm and lemon balm N. menthoides herbs did not decrease menstrual bleeding in students with premenstrual syndrome. However, further clinical studies should be performed to assess the efficacy of lemon balm and N. menthoides in reproductive women to determine whether this medication is appropriate for treatment in the clinical setting.