Design: Systematic review and meta-analysis of randomised trials
Population: 8 trials of men with acute urinary retention due to BPH
Primary outcome: Successful trial without catheter
Effect: Risk difference +24.5% (95% CI 18.4–30.7) vs placebo

This meta-analysis pooled eight randomised trials comparing an alpha-1 blocker with placebo in men catheterised for acute urinary retention due to benign prostatic hyperplasia, with trial without catheter as the outcome.

Alpha-blockers increased the chance of voiding successfully after catheter removal by an absolute 24.5 percentage points (95% CI 18.4–30.7). The authors report that they also appeared to reduce recurrence of retention, without a significant increase in adverse events.

The abstract does not report heterogeneity or trial quality, so how consistent the trials were is unclear. The effect is large and consistent with existing practice, and the drugs are cheap and widely available in India. The practical message is simple: a man catheterised for BPH-related retention should start an alpha-blocker before his trial without catheter, with a warning about postural dizziness. It was published on 28 September 2026.

Start an alpha-blocker such as tamsulosin when a man is catheterised for BPH-related acute retention.
Give it for at least a few days before attempting trial without catheter.
Warn about postural dizziness, especially in older men and those on antihypertensives.
Ask about planned cataract surgery; alpha-blockers raise the risk of floppy iris syndrome.
Arrange urology follow-up for men who fail the trial or have recurrent retention.

Why it matters

One cheap tablet raises the chance a man goes home without a catheter by about a quarter.

The statistics, in plain English

A risk difference of 24.5 percentage points means about one extra successful trial without catheter for every four men treated. The confidence interval (18.4–30.7) is well away from zero, so chance is an unlikely explanation.