Causes of Overactive Bladder
Several medical conditions cause the symptoms of overactive bladder. Overactive bladder is characterized by frequent urination, urinary urgency, leaking, and incontinence of urine. The excessively frequent urination associated with overactive bladder may be voluntary or involuntary and may involve small or large amounts of urine.
Overactive bladder is caused by excessive or frequent contraction of the bladder muscle. This happens when the muscles of the bladder produce a sensation of fullness of the bladder, which normally triggers an urge to urinate. Normally, a full bladder gives you some feedback that you should voluntary urinate fairly soon. People who have overactive bladder get the sensation of a full bladder and need to empty it very quickly. Sometimes, with overactive bladder, the bladder actually releases urine before there is time to reach a toilet and sometimes the bladder releases urine involuntarily or without warning.
Overactive contraction of the bladder muscles is a characteristic of overactive bladder. Muscle contraction is muscle shortening, which means muscle activity. Normally, muscle contraction, caused by the presence of urine in the bladder, stimulates the sensation that you need to urinate. When you have that sensation, you typically have a bit of time to reach a toilet and to voluntarily urinate. If you have an overactive bladder, you may get that sensation frequently, even when the bladder is not full. Sometimes, the bladder muscle contraction can make you feel that you have to go urinate immediately. And sometimes the contraction can even stimulate involuntary urination in small or large amounts. There are a number of situations that make this excessive or frequent overactivity of the bladder muscle more likely.