Medical treatment for the symptoms of benign prostatic hyperplasia (BPH) consists of a blockers and 5-alpha-reductase inhibitors. Data suggest that 5-alpha-reductase inhibitors can prevent progression of BPH and reduce the risk of BPH-related surgery, especially in men with large-volume prostates. Results from the largest randomized, prospective, placebo-controlled trial, the Medical Therapy of Prostatic Symptoms trial, have been presented. These results support the notion of using 5-alpha-reductase inhibitors for the prevention of BPH progression and BPH-related surgery. Furthermore, long-term 5-alpha-reductase inhibitor monotherapy, although slow in onset, is a viable therapy for symptom relief in men with mild to moderate symptoms.