To review the available evidence concerning the use of anticholinergic drugs, alone or in combination with alpha-blockers, in patients with lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) and concomitant overactive bladder syndrome, to assess whether the currently available evidence suggests a role for antimuscarinic drugs in patients with BPH.

A systematic review of the literature was performed using Embase, MEDLINE, and Web of Science through a complex search strategy including "free text" and "MeSH" protocols. Moreover, the Cochrane database of systematic review was browsed for records regarding BPH and the abstract books of the American Urological Association, European Association of Urology, and International Continence Society annual meetings from 2000 to 2005 were hand-searched for studies concerning the topic of the review.

From the literature search, we identified four randomised controlled trials (RCTs), two prospective case series, and a few congress abstracts. For methodologic issues, the best RCT was based on urodynamic data, but did not provide any clinical insight on the patients' symptoms. The other papers were affected by significant methodologic or clinical drawbacks.

The available data may be considered promising in terms of safety and efficacy. The evidence of the limited number of RCTs available, considering their methodologic or clinical shortcomings, is not sufficient to support the clinical use of combination therapy with alpha-blockers and anticholinergic drugs in patients with associated storage and voiding symptoms. Well-designed, large, double-blind, placebo-controlled, long-term RCTs are needed to assess the long-term safety and efficacy of antimuscarinic drugs, alone or in combination with alpha-blockers, in this category of patients.