The most widely used phytotherapeutic agent for the treatment of BPH is the extract of the American saw palmetto or dwarf palm plant, Serenoa repens. Several studies have demonstrated that Serenoa repens exerts its biological activity through several mechanisms of action, including antiestrogenic and antiandrogenic effects, anti-inflammatory effects, and a decrease in available sex hormone-binding globulin. This evidence concerns the gene SHBG and benign prostatic hyperplasia.