Update on Phosphodiesterase Type 5 Inhibitors for the Treatment of Lower Urinary Tract Symptoms due to Benign Prostatic Hyperplasia.

Many aging men will experience both erectile dysfunction (ED) and benign prostatic hyperplasia (BPH), resulting in lower urinary tract symptoms (LUTS). Basic and clinical evidence suggests common pathogenic mechanisms underlying both LUTS and ED. Decreases in the nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway with age result in decreased levels of intracellular cGMP and calcium, leading to diminished smooth muscle relaxation of the bladder and prostate and worsening LUTS. Phosphodiesterase type 5 inhibitors as monotherapy in combination with α-blockers have shown efficacy in treating both LUTS and ED. Tadalafil has recently been approved by the US Food and Drug Administration for the treatment of LUTS secondary to BPH, with or without concomitant ED.