There are several types of urinary incontinence, which are classified according to the symptoms experienced and circumstances at the time of the urine leakage. They are:

• Stress incontinence. Occurs when an increase in pressure in the abdomen from activities such as exercising, coughing, sneezing and laughing forces the urinary sphincter (the ring of muscles that surrounds the urethra) to open, causing urine to leak. It is the most common form of incontinence. This opening of the muscle can be the result of an actual problem with the muscle or it can be caused by the muscle becoming displaced from abdominal pressure (e.g., coughing, sneezing).
  
  
• Urge incontinence. Occurs when the bladder contracts when it should not, causing an abrupt, overwhelming urge to urinate followed by urine leakage. The urge and leakage often occur in response to a stimulus, such as going out in the cold, turning on the faucet or washing hands. Urge incontinence is a symptom of overactive bladder (OAB), a condition characterized by involuntary bladder contractions during the time the bladder is filling.
  
  
• Mixed incontinence. Occurs when the patient has more than one type of incontinence, usually stress and urge incontinence. One of the types is usually more bothersome than the other.
  
  
• Overflow incontinence. Occurs when the bladder fails to empty properly, either because of obstruction or weak bladder muscle contractions. When the patient tries to urinate, abnormally large amounts of urine remain in the bladder. A weak urine stream, dribbling or frequent urination are symptoms of this condition.
  
  
• Reflex incontinence. Occurs when people with a neurological injury (such as paralysis) experience urinary incontinence without any warning signals.
  
  
• Functional incontinence. Occurs when physical or mental disabilities prevent patients from getting to the toilet in time. This is common in older adults, especially those in nursing facilities.
  
  
• Transient incontinence. Leakage resulting from a temporary condition, such as a urinary tract infection. The incontinence is short-term and typically ends when the condition passes.
  
  
• Nocturnal enuresis (or nighttime incontinence). Some toilet-trained children, mostly boys, experience nighttime incontinence for a variety of reasons. Adults can also experience nighttime incontinence due to drinking excessive alcohol or taking certain types of medications. Older adults sometimes experience nighttime incontinence because aging bladders can have difficulty storing urine.