Effect of Zingiber officinale R. rhizomes (ginger) on pain relief in primary dysmenorrhea: a placebo randomized trial

Background: Zingiber officinale R. rhizome (ginger) is a popular spice that has traditionally been used to combat the effects of various inflammatory diseases. The aim of this study was to evaluate the effects of ginger on pain relief in primary dysmenorrhea. Method: This was a randomized, controlled trial. The study was based on a sample of one hundred and twenty students with moderate or severe primary dysmenorrhea. The students were all residents of the dormitories of Shahed University. They were randomly assigned into two equal groups, one for ginger and the other for placebo in two different treatment protocols with monthly intervals. The ginger and placebo groups in both protocols received 500 mg capsules of ginger root powder or placebo three times a day. In the first protocol ginger and placebo were given two days before the onset of the menstrual period and continued through the first three days of the menstrual period. In the second protocol ginger and placebo were given only for the first three days of the menstrual period. Severity of pain was determined by a verbal multidimensional scoring system and a visual analogue scale. Results: There was no difference in the baseline characteristics of the two groups (placebo n = 46, ginger n = 56). The results of this study showed that there were significant differences in the severity of pain between ginger and placebo groups for protocol one (P = 0.015) and protocol two (P = 0.029). There was also significant difference in duration of pain between the two groups for protocol one (P = 0.017) but not for protocol two (P = 0.210). Conclusion: Treatment of primary dysmenorrhea in students with ginger for 5 days had a statistically significant effect on relieving intensity and duration of pain. Trial registration: IRCT201105266206N3