Epilobium angustifolium L. extract with high content in oenothein B on benign prostatic hyperplasia: A monocentric, randomized, double-blind, placebo-controlled clinical trial

Biomed Pharmacother. 2021 Jun;138:111414. doi: 10.1016/j.biopha.2021.111414. Epub 2021 Mar 23.


Benign prostatic hyperplasia (BPH) is a common condition in adult men. Especially in Europe, increasing attention has been focused on E. angustifolium extracts (EAEs), which are widely used for their positive effects on the symptoms of BPH, although human clinical trials are limited. The aim of this monocentric, randomized, double-blind, placebo-controlled clinical trial is to evaluate if a daily intake of hard, gastric-resistant capsules containing a chemically characterized EAE (500 mg) for 6 months may allow a significant improvement in symptoms in subjects with BPH. This study was conducted in 128 adult men, randomly assigned to receive either EAE food supplement (N = 70) or placebo (N = 58), who underwent four visits (baseline = t0, after 15 days = t1, after 2 months = t2 and after 6 months = t3) in an outpatient setting to evaluate post-void residual (PVR) and prostate volume (PV) by means of prostate ultrasound, prostate-specific antigen (PSA) and neutrofile/lymphocyte ratio (N/L), nocturia before the clinical visits and International Prostate Specific Score (IPSS) registered by the physicians. EAE food supplement induced a significant decrease in the PVR and consequently nocturia improving the quality of life as suggested by the decrease of IPSS. No subjects reported adverse effects related to oral intake of EAE food supplement. Moreover, EAE food supplement did not show hepatic or renal toxicity. In conclusion, EAE food supplements can be used in subjects with BPH, to improve their quality of life and general renal function.

Keywords: Benign prostatic hyperplasia; Epilobium angustifolium L. extract; LC-MS metabolic profile; Oenothein B; Randomized double-blind placebo-controlled clinical trial.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Double-Blind Method
  • Epilobium*
  • Humans
  • Hydrolyzable Tannins / isolation & purification
  • Hydrolyzable Tannins / pharmacology
  • Hydrolyzable Tannins / therapeutic use*
  • Male
  • Middle Aged
  • Onagraceae*
  • Plant Extracts / isolation & purification
  • Plant Extracts / pharmacology
  • Plant Extracts / therapeutic use*
  • Prostate / drug effects*
  • Prostate / metabolism
  • Prostate / pathology
  • Prostatic Hyperplasia / blood
  • Prostatic Hyperplasia / drug therapy*
  • Prostatic Hyperplasia / pathology


  • Hydrolyzable Tannins
  • Plant Extracts
  • oenothein B