Effects of a standardised extract of Trifolium pratense (Promensil) at a dosage of 80mg in the treatment of menopausal hot flushes: A systematic review and meta-analysis

Phytomedicine. 2017 Jan 15;24:141-147. doi: 10.1016/j.phymed.2016.12.003. Epub 2016 Dec 12.


Objective: To critically assess the evidence for a specific standardised extract of Trifolium pratense isoflavones (Promensil) at a dosage of 80mg/day in the treatment of menopausal hot flushes.

Data sources: Systematic literature searches were performed in Medline, Scopus, CINAHL Plus, Cochrane, AMED and InforRMIT and citations obtained from 1996 to March 2016. Reference lists were checked; corresponding authors contacted and the grey literature searched for additional publications.

Review methods: Studies were selected according to predefined inclusion and exclusion criteria. All randomised clinical trials of a specific standardised extract of Trifolium pratense isoflavones (Promensil) used as a mono-component at 80mg/day and measuring vasomotor symptoms were included. The data extraction and quality assessment were performed independently by one reviewer and validated by a second with any disagreements being settled by discussion. Weighted mean differences and 95% confidence intervals were calculated for continuous data using the fixed-effects model.

Results: Twenty potentially relevant papers were identified, with only five studies meeting the inclusion criteria. The meta-analysis demonstrated a statistical and clinically relevant reduction in hot flush frequency in the active treatment group compared to placebo. Weighted mean difference 3.63 hot flushes per day: [95% CI 2.70-4.56]; p˂0.00001). Due to a lack of homogeneity a priori defined sub-group analyses were performed demonstrating a substantive difference between cross-over and parallel-arm clinical trial designs.

Conclusion: There is evidence for a statistical and clinically significant benefit for using a specific standardised extract of red clover isoflavones (Promensil) at 80mg/day for treating hot flushes in menopausal women across the 3 studies included in the meta-analysis. The preparation was safe over the short-term duration of the studies (3 months).

Keywords: Hot flushes; Isoflavones; Menopause; Red clover; Standardisation; Trifolium pratense.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Dose-Response Relationship, Drug
  • Female
  • Hot Flashes / drug therapy*
  • Humans
  • Isoflavones / therapeutic use*
  • Menopause / physiology*
  • Phytotherapy
  • Plant Extracts / therapeutic use*
  • Time Factors
  • Trifolium / chemistry*


  • Isoflavones
  • Plant Extracts