**7.3.4 Phytotherapy**

The use of plant-derived agents (*Serenoa repens* or Saw palmetto, *Pygeum africanum*) on LUTS and BPH has been popular in Europe for many years and has recently spread in the USA. Their mechanism of action is still unclear. However they seem to improve urinary symptoms without important side effects. In some studies the efficacy of these compounds was found to be equivalent to 5-ARIs and alpha-blockers (Lowe 2001; Debruyne, Koch et al. 2002). The most widely studied and used, *Serenoa repens*, has no effect on prostate volume or the PSA test, but slightly decreases the prostate epithelium. It does not cause erectile dysfunction, but the herb may aggravate chronic gastrointestinal disease such as peptic ulcer (Bent, Kane et al. 2006).
