Which drug interaction increases urinary incontinence risk in older women?

• A. Beta-blockers with loop diuretics
• B. ACE inhibitors with ARBs
• C. Non-selective peripheral alpha-1 blockers with loop diuretics
• D. SSRIs with SNRIs

Answer: (C)

The key idea is that certain drug combinations can worsen urinary continence by both increasing urine production and reducing the outlet resistance that keeps urine in. Non-selective peripheral alpha-1 blockers relax smooth muscle in the bladder neck and urethra, which lowers outlet resistance and makes leakage more likely. Loop diuretics raise urine volume and urgency. Put together, older women—who may already have pelvic floor weakness or baseline incontinence—are at higher risk for urinary leakage with this combo.

Other options don’t create that specific interaction: combining beta-blockers with loop diuretics mainly raises risks like dizziness or hypotension; ACE inhibitors with ARBs is mainly a blood pressure/kidney risk without affecting continence; SSRIs with SNRIs involve mood or hyponatremia concerns, not urinary incontinence through this mechanism.