Efficacy and safety of a combination of Sabal and Urtica extract in lower urinary tract symptoms--long-term follow-up of a placebo-controlled, double-blind, multicenter trial

Int Urol Nephrol. 2007;39(4):1137-46. doi: 10.1007/s11255-006-9173-7. Epub 2007 Feb 15.


In an open-label extension of a randomized, double-blind clinical trial, the long-term efficacy and tolerability of a fixed combination of 160 mg Sabal fruit extract WS 1473 and 120 mg Urtica root extract WS 1031 per capsule (PRO 160/120) were investigated in elderly men with moderate or severe lower urinary tract symptoms (LUTS) caused by benign prostatic hyperplasia (BPH). Two hundred and fifty-seven patients were randomly treated with 2 x 1 capsule/day PRO 160/120 or placebo for 24 weeks, followed by a 24-week control period and a 48-week follow-up period in which all patients received PRO 160/120. Efficacy measures included the assessment of LUTS [International Prostate Symptom Score ((I-PSS) self-rating questionnaire] and uroflow and sonographic parameters. Two hundred and nineteen subjects participated in the follow-up. Between baseline and end of observation (week 96) the I-PSS total score was reduced by 53% (P < 0.001), peak and average urinary flow increased by 19% (P < 0.001), and residual urine volume decreased by 44% (P = 0.03). The incidence of adverse events during follow-up was one in 1,181 treatment days; in only one event a causal relationship with intake of PRO 160/120 could not be excluded. Treatment with PRO 160/120 thus provides a clinically relevant benefit over a period of 96 weeks.

Publication types

  • Clinical Trial, Phase III
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Disease Progression
  • Double-Blind Method
  • Follow-Up Studies
  • Humans
  • Male
  • Phytotherapy / methods*
  • Plant Extracts / adverse effects
  • Plant Extracts / therapeutic use*
  • Prostatic Hyperplasia / complications
  • Serenoa*
  • Severity of Illness Index
  • Statistics, Nonparametric
  • Time Factors
  • Treatment Outcome
  • Urination Disorders / drug therapy*
  • Urination Disorders / etiology
  • Urination Disorders / physiopathology
  • Urodynamics
  • Urtica dioica*


  • Plant Extracts