Randomised trial, 2019
Does peppermint oil reduce PMS symptoms?
Yes. Peppermint oil significantly reduced PMS severity compared to placebo, with only about 2 women needing treatment for every 1 who benefited.
What they did
Randomized, double-blind, placebo-controlled trial. 50 high school students with PMS in Iran were assigned to take either peppermint oil capsules (Colpermin, 187 mg peppermint oil) or placebo twice daily from day 15 of one menstrual cycle to day 1 of the next cycle for 2 cycles. PMS was assessed using Delany's PMS checklist.
What they found
PMS score decreased from 30.3±10.1 to 15.5±6.0 in the peppermint oil group and from 23.2±7.0 to 20.7±8.0 in the placebo group over 2 cycles. Mean difference between groups was -9.77 (95% CI: -12.52 to -7.02, P<0.0001). Number needed to treat was approximately 2.
What it means for you
Peppermint oil capsules appear to be safe and effective at reducing PMS severity, meaning roughly 2 women need treatment for 1 to see significant improvement. The study was small (50 people) and included only high school students in Iran, so results may not apply to all women.
50
High school students studied
187 mg
Peppermint oil per capsule
NNT=2
Number needed to treat
About the study
- Original title
- Effect of Peppermint Oil on Premenstrual Syndrome: A Randomized, Double-Blind Placebo-Controlled Study
- Authors
- Mouloud Agajani Delavar, Soheila Ebrahimi, Sedigheh Esmaeilzadeh et al.
- Journal
- Iranian Red Crescent Medical Journal
- Year
- 2019
- Study design
- Randomised trial
- Participants
- 50
- What was tested
- Colpermin peppermint oil capsules (187 mg) twice daily from day 15 of menstrual cycle to day 1 of next cycle for 2 cycles
- Open access
- Yes
- Read the paper
- doi.org/10.5812/ircmj.84657
Topics
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