Enuresis is the medical term for involuntary urination or "wetting". It can occur during the day (diurnal enuresis) or at night (nocturnal enuresis), and it is more commonly known as bed-wetting. Enuresis can be caused by a variety of factors, including disorders of the kidneys, bladder, or ureter, poor control of the muscles that control the release of urine, and neurological disorders such as Tourettes syndrome. Involuntary release of urine may also result from a small bladder, persistent urinary tract infections, severe stress, or developmental delays that interfere with toilet training. Voluntary enuresis may be associated with other mental disorders, including behavior disorders or emotional disorders such as anxiety.

Enuresis is a common childhood problem, affecting about 15% of all 5-year-olds, 7% of all 8-year-olds, and 3% of 12-year-olds. Most children outgrow this problem by the time they become teens, with only about 1% of males and less than 1% of females having the disorder at age 18.

Enuresis is usually diagnosed based on a complete medical history and physical examination of the child. Urine tests, blood pressure measurement, and blood tests may also be performed to help rule out other causes for the wetting. Treatment for enuresis will depend on the childs age, overall health, and medical history, as well as the extent of the condition and the childs tolerance for specific medications, procedures, or therapies. In mild cases, treatment may not be needed, as most children outgrow the condition. However, medications and behavioral therapies are available to treat more severe cases.