The latest in clinical trial results of 5-alpha reductase inhibitors in combination regimens for benign prostatic hyperplasia.

Introduction: BPH/male LUTS is a prevalent condition in the aging male population with multifactorial pathophysiology. Pharmacotherapy remains the cornerstone of treatment in patients who fail conservative treatment. 5-α-Reductase inhibitors (5-ARIs) are the only class of medication shown to reduce the risk of acute retention and BPH-related surgery and, thus, are commonly used along with other "short acting" medications in combination treatments.

Areas covered: Combination treatments with α-blockers and 5-ARIs have been investigated extensively in high quality trials that prove the long-term efficacy of such treatments with acceptable rates of side effects. Combination treatments involving 5-ARIs and other classes of medications (anticholinergics, b3 agonists, PDEI) have been shown to be beneficial in the short term and but studies with longer follow-up periods are required to fully establish their role.

Expert opinion: A-blocker/5-ARI combination treatment is a reasonable approach for patients with male LUTS/BPH who are at increased risk of disease progression or have incomplete response to monotherapies. Other combination treatments with 5-ARIs and PDEI or anticholinergics/β-3 agonists can be tried based on predominant symptoms or side effect profile, but patients should be informed about the lack of long-term data.