Overactive bladder does not yet have a defined cause. It can occur in children and adults. It is clinically characterized by the presence of urinary urgency, i.e. the compelling urge to urinate. This leads many people to experience urinary incontinence if they don't go to the toilet immediately. This symptom is called urge incontinence. It is also common for people to have increased urinary frequency, sometimes more than 20 times a day. Many have nocturia, which is the act of waking up at night to urinate. It is also often associated with symptoms of anxiety and depression.
