PURPOSE OF REVIEW: Phosphodiesterase 5 (PDE-5) inhibitors are established as first-line therapy in erectile dysfunction. There is emerging evidence that they may have a role in treating patients with lower urinary tract symptoms (LUTS) from benign prostatic hypertrophy. RECENT FINDINGS: All three commonly used PDE-5 inhibitors (sildenafil, vardenafil and tadalafil) appear to improve LUTS as measured by the International Prostate Symptom Score. However, to date, no change in urinary flow rates have been demonstrated. SUMMARY: Erectile dysfunction and LUTS frequently coexist in men of advancing age. There appears to be an emerging role for PDE-5 inhibitors as a treatment for both conditions. Further studies are required to elicit the exact mechanism of action in LUTS.