More than half of Americans age 65 or older report they have urinary or bowel incontinence — about 25 percent with severe bladder leakage, and about 8 percent with moderate to severe bowel leakage [source: Reinberg]. Despite the numbers, incontinence isn't, or at least doesn't have to be, a part of aging.
There are two main types of urinary incontinence. Stress incontinence is usually mild leakage, and it usually happens alongside an activity that increases the pressure on your abdomen, such as coughing or laughing. Stress incontinence often develops after the pelvic floor muscles are stretched or weakened, and it's common after childbirth.
Urge incontinence, also called an overactive bladder, has a very different list of causes and symptoms than stress incontinence. Patients with urge incontinence experience strong and immediate urges to urinate. These patients sometimes involuntarily experience their overactive bladder voiding its entire contents, which, for an average adult, is probably about 2 cups of urine, a little less than half a liter [source: Miller].
Urinary incontinence is treated with three types of drugs: anticholinergics, antispasmodics and tricyclic antidepressants (TCAs). Imipramine (Tofranil), a TCA, helps increase the levels of serotonin and other brain chemicals, which reduces the symptoms of urge incontinence by smoothing and contracting the muscles of the bladder.
While not effective for treating the symptoms of urge incontinence, another TCA, amitriptyline (Elavil), is effective in relieving pelvic floor spasms and pelvic floor muscle dysfunction in women with stress incontinence.
Between 54 and 64 percent of women with incontinence report fewer urinary leaks when prescribed a different type of antidepressant: duloxetine (Cymbalta), a selective serotonin-noradrenaline reuptake inhibitor (SNRI). Duloxetine reduces the symptoms of stress incontinence by contracting the urethral sphincters during what's called the "storage phase" of the urination cycle [source: Weiss].