The efficacy of lemon balm (Melissa officinalis L.) alone and combined with lemon balm—Nepeta menthoides on premenstrual syndrome and quality of life among students: A randomized controlled trial

The purpose of this study was to assess the efficacy of Melissa officinalis, both alone and in combination with Nepeta menthoides, on premenstrual syndrome (PMS) and associated quality of life.A total of 93 female students from Tabriz University of Medical Sciences, Iran, were included in the study. The participants completed the Daily Record of Severity of Problems questionnaire for two consecutive menstrual cycles to establish the presence and severity of PMS symptoms. Participants were then randomly divided into three groups, two intervention groups and one placebo, with each group containing 31 subjects. The intervention groups received either a 500 mg capsule of M. officinalis or a capsule containing a combination of 250 mg of M. officinalis and 250 mg of Nepeta menthoides, whilst the placebo group received a 500 mg capsule of starch powder. Capsules were taken twice daily during the luteal phase of two consecutive menstrual cycles.The decrease in the mean scores of PMS symptoms in the first [adjusted difference: −55.5 (95% confidence interval, −96.8 to −14.1)] and second [−57.3 (−99.9 to −14.7)] month after intervention in the lemon balm group was significantly greater than that in the placebo group. There was, however, no statistically significant difference between the M. officinalis/N. menthoides and placebo groups after intervention. In addition, the mean scores of the physical and psychological aspects of quality of life in the M. officinalis and M. officinalis/N. menthoides groups were significantly greater than those of the placebo group at the end of the second month of treatment. The results of this study suggest that M. officinalis can reduce the severity of symptoms in women with PMS.