Irritable bladder, also called overactive bladder, is a disruption of the normal process of filling and emptying the bladder. Normally, the detrusor muscle of the bladder relaxes while the bladder fills with urine, reports the American Urological Association. However, when the detrusor muscle contracts more often than normal, the patient feels sudden, frequent urges to urinate during the day and at night and may experience urine leakage. Although the pathology of overactive bladder is unknown, underlying causes of the symptoms have been identified.
Obstruction
Factors that obstruct bladder outflow, including an enlarged prostate, bladder stones, constipation or previous pelvic surgery, may contribute to irritability of the bladder, notes the Mayo Clinic. About half of all men with prostate obstruction also have overactive bladders, according to Dr. Matt Rosenberg in the May 2007 issue of the “Cleveland Clinic Journal of Medicine, but further research is needed in this area.
Drug Side Effects
Medications, such as diuretics, that cause a rapid increase in urine production and those that require that large amounts of fluids be taken with them can produce the symptoms of overactive bladder, according to the Mayo Clinic. Excessive use of caffeine or alcohol produces a diuretic effect, notes Dr. Rosenberg, which leads to frequency and urgency. Other medications, including sedatives and anti-psychotics, may relax the detrusor muscle as well.
Nerve Damage or Neurological Disease
A history of neurological disorders and injuries, such as Parkinson's disease, spinal cord injury, dementia, stroke, neurogenic bladder or multiple sclerosis, is often associated with an overactive bladder, according to Dr. Rosenblatt. Some medications used to treat neurological diseases can also contribute to urinary difficulties, including an overactive bladder. Treatment by a specialist is indicated for these patients.
Urinary Tract Infection
Infections of the urinary tract cause inflammation that produces a strong, persistent urge to urinate and frequent voiding, reports the Mayo Clinic. Associated symptoms include burning with urination, cloudy or discolored urine, pain, and strong-smelling urine. Treatment of the infection provides relief of the symptoms.
Associated Conditions
Irritable bladder may occur more often in patients with depression, anxiety, attention deficit disorder, irritable bowel syndrome, pain and fibromyalgia than in the general population, reports the American Urological Association. More research is needed in this area to determine cause and effect relationships. Conditions with similar symptoms, including diabetes, bladder cancer and congestive heart failure, must also be ruled out, according to Dr. Rosenblatt.
