Permixon, the lipidosterolic extract of Serenoa repens, is widely used for the treatment of symptoms associated with benign prostatic hyperplasia (BPH). This open study assessed the efficacy and tolerability of Permixon 160 mg twice daily administered for 2 years. One hundred fifty-five men with clinically diagnosed BPH and complaints of prostatic symptoms were enrolled in the study. At 6, 12, 18, and 24 months, the International Prostate Symptom Score (I-PSS), quality of life, and sexual function score were recorded, and urodynamics and biologic values were measured. Adverse events were recorded every 3 months. I-PSS and quality of life improved significantly from baseline at each evaluation time point. At the end of the study and at each evaluation, maximum urinary flow also improved significantly. Prostate size decreased. Sexual function remained stable during the first year of treatment and significantly improved (P = .001) during the second year. Prostate-specific antigen was not affected, and no changes in plasma hormone levels were observed. Nine patients reported 10 adverse events, none related to treatment. Improvements in efficacy parameters began at 6 months and were maintained up to 24 months. These data demonstrate the long-term efficacy and tolerability of Permixon and support its use as a first-line medical therapy for uncomplicated symptomatic BPH.