Enuresis is defined as the voluntary or involuntary repeated discharge of urine into clothes or bed after a developmental age when bladder control should be established. Most children with a mental age of 5 yr have obtained bladder control during the day and night. The diagnosis of enuresis is made when urine is voided twice a week or more for at least 3 consecutive months or when clinically significant distress occurs in areas of the child's life as a result of the wetting. Primary nocturnal enuresis (NE): refers to involuntary loss of urine during sleep in patients who have never achieved a sustained period of dryness. Secondary NE is enuresis that develops after a patient has achieved a sustained period of bladder control. The pathogenesis of NE has centered on three hypotheses; children who wet at night sleep deeply, have small bladder capacity and/or have nocturnal polyuria secondary to lack of the physiological nocturnal peak of vasopressin.