Urinary Side Effects of Duloxetine in the Treatment of Depression and Stress Urinary Incontinence

Background: The efficacy and safety of duloxetine, a dual reuptake inhibitor of serotonin and norepinephrine at the recommended starting dose, have been demonstrated in the treatment of major depressive disorder (MDD) in men and women and in the treatment of stress urinary incontinence (SUI) in women. Since the mechanism of action of duloxetine in the treatment of SUI is believed to be related to enhanced urethral closure forces, it is important to clarify the risk of acute urinary retention.

Method: The relationship between duloxetine and obstructive voiding symptoms was examined in 8 double-blind, 8- to 9-week, placebo-controlled studies and 1 open-label study in men and women treated for MDD with duloxetine 40 to 120 mg/day and in 4 double-blind, 12-week, placebo-controlled studies and 4 ongoing open-label studies in women treated for SUI with duloxetine 80 mg/day.

Results: In 378 men and 761 women with MDD treated in placebo-controlled trials, 0.4% (4/1139; 3 men and 1 woman) of those treated with active medication reported subjective urinary retention versus none (0/777) of those treated with placebo (p = .15). In 958 women with SUI treated with duloxetine in placebo-controlled trials, none reported subjective urinary retention. Overall, in the duloxetine placebo-controlled clinical studies in the treatment of MDD and SUI, obstructive voiding symptoms (reported either as subjective urinary retention or other obstructive voiding symptoms) occurred more often in patients receiving duloxetine (1.0%, 20/2097) than in patients receiving placebo (0.4%, 6/1732) (p < .05). Of the 4719 MDD and SUI patients treated with duloxetine in placebo-controlled and ongoing open-label studies, 2 men and 1 woman discontinued because of obstructive voiding symptoms. Although such an evaluation was not required by protocol, no cases of objective acute urinary retention with postvoid residual urine verified with a bladder scan or requiring catheterization were reported in patients treated with duloxetine.

Conclusion: Duloxetine treatment in women and men with depression and in women with SUI was rarely associated with obstructive voiding symptoms, and no subjects had objective acute urinary retention requiring catheterization.