OBJECTIVE To determine the efficacy of oral extended-release oxybutynin for urge urinary incontinence in older female nursing home residents with mild to severe cognitive impairment. METHODS Randomized, double-blind, placebo-controlled trial. METHODS Twelve skilled nursing homes. METHODS Fifty women aged 65 and older with urge incontinence and cognitive impairment. METHODS Four-week treatment with daily oral extended-release oxybutynin 5 mg or placebo. METHODS Urinary incontinence episodes, urinary frequency, and total dryness assessed hourly over two 8-hour days (8 AM TO 4 PM), and evening and night nursing staff ratings of urinary symptoms. RESULTS Of the participants, 96% (n = 25) on oxybutynin and 92% (n = 22) on placebo completed the trial. Compared with baseline, both groups achieved a significant median decrease in mean urinary incontinence episodes and urinary frequency at 4 weeks (P = .01-.05). There were no significant between-group differences in any urological outcome. In the exploratory analysis, there were no significant differences from baseline or placebo in any urological outcome with oxybutynin in participants with mild to moderate cognitive impairment and/or adequate mobility compared with participants with more severe cognitive and physical impairment. Staff ratings found that more participants had improvement in urinary symptoms from baseline with oxybutynin than placebo but significant only for delaying evening voiding (P = .02). CONCLUSIONS Extended-release oxybutynin 5 mg per day for 4 weeks in older cognitively impaired female nursing home residents did not significantly reduce urinary incontinence and urinary frequency or achieve dryness. Participants with mild to moderate cognitive and/or physical impairment were no more likely to benefit from oxybutynin than more severely impaired individuals in an exploratory analysis but further research in a larger population and perhaps using a larger dose is needed.