Randomised trial, 2016
Does St. John's Wort or vitamin B6 treat premenstrual syndrome better than placebo?
Both St. John's Wort and vitamin B6 reduced PMS symptoms more effectively than placebo. St. John's Wort reduced symptoms by 40%, vitamin B6 by 38%, and placebo by 29%.
What they did
A double-blind randomized controlled trial with 238 women with PMS in Iran. Women tracked their symptoms for 2 months before being randomly assigned to one of three groups. One group took St. John's Wort tablets (containing 330 µg hypericin), one took vitamin B6 tablets (40 mg), and one took placebo. All took their assigned treatment from day 1 to day 30 of their menstrual cycle for two cycles.
What they found
The average symptom score decreased by 40% in the St. John's Wort group, by 38% in the vitamin B6 group, and by 29% in the placebo group. All three groups showed significant improvement compared to their starting point. The St. John's Wort and vitamin B6 groups showed significantly more improvement than placebo.
What it means for you
Both St. John's Wort and vitamin B6 are effective treatments for moderate to severe PMS and are well tolerated. They work similarly well. However, this study was conducted in Iran in one hospital setting, so results may not apply in other countries or settings. The notable improvement with placebo (29%) is common in PMS studies.
40%
Symptom reduction with St. John's Wort
38%
Symptom reduction with vitamin B6
29%
Symptom reduction with placebo
About the study
- Original title
- Hypericum perforutum and Vitamin B6 as a Treatment for Premenstrual Syndrome
- Authors
- Masumeh Ghazanfarpour, Somayeh Abdolahian, Talat Khadivzadeh et al.
- Journal
- Jundishapur Journal of Natural Pharmaceutical Products
- Year
- 2016
- Study design
- Randomised trial
- What was tested
- St. John's Wort (330 µg hypericin), vitamin B6 (40 mg), or placebo for 2 menstrual cycles.
- Open access
- Yes
- Read the paper
- doi.org/10.5812/jjnpp.34093
Topics
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