Underactive bladder

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at August 25, 2016
StartDiseasesUnderactive bladder

Though many people have heard of overactive bladder syndrome, underactive bladder or underactive bladder syndrome can be just as troubling. Both conditions are caused when the muscles that control the bladder do not operate the way they should. This is because the nerves that control those muscles are not communicating properly with the brain. Underactive bladder is also called detrusor underactivity or UAB.


Definition & Facts

Underactive bladder syndrome is one of the conditions that fall under the rubric of neurogenic bladder. Patients with these conditions cannot tell when their bladder is full and don't contract the muscles in a way that can help the bladder empty completely. Most patients are between 40 and 60 years old, but people younger or older can be stricken with UAB.

Symptoms & Complaints

People with underactive bladder find that they take a longer than usual time to empty their bladder. Sometimes, only a bit of urine is excreted even though the bladder is unusually full, and the patient has to exert themselves to push the urine out. Complications of this condition can be urinary tract infections and painful urinary retention.


There are many causes of underactive bladder syndrome. Some of them are present at birth (congenital) and include:

  • Myelomeningocele type of spina bifida. In this condition, the spine of a fetus does not develop properly during the early stages of pregnancy. This manifests as a myelomeningocele – a bulge that protrudes through an opening in the spine that is full of cerebrospinal fluid, bits of the spinal nerves and meninges, which are the membranes that protect the baby's spinal cord. A myelomeningocele is most often found in the lumbar back and is the most serious type of spina bifida.
  • Cerebral palsy results when injuries occur to the areas of the brain that control the patient's motor functions and posture. The injuries can happen before birth, during birth or after birth.
  • Diabetes mellitus. UAB is often a complication of diabetes. The condition is called diabetic cystopathy. With this condition, the patient cannot tell if their bladder is full. At the same time, the bladder is able to hold more urine, but it does not contract as well as it should. It can retain urine even after the patient has voided.
  • Bladder outlet obstruction. UAB can be the result of something obstructing the ducts that transport urine out of the bladder. Sometimes this is caused by an enlarged prostate (benign prostatic hyperplasia) in a man. It can also be caused by prostate cancer. With women, a vaginal prolapse can block the ducts. A uterine prolapse occurs when the uterus drops from its normal location and bulges into the vagina. This can interfere with the functioning of the bladder.
  • Aging. It's not unusual for the bladders of elderly people to stop contracting the way they used to. This can lead to an underactive bladder.
  • Guillain-Barré syndrome is an inflammatory condition that affects the nerves and causes weakness and loss of sensation. It sometimes happens one to four weeks after surgery or an infection. Underactive bladder is one of its first symptoms, and is sometimes so severe that the patient needs to wear a catheter. However, the condition is not chronic, and most patients recover.

Other conditions that can cause underactive bladder are stroke, multiple sclerosis, and Parkinson's disease. All of these conditions affect the nerves that control the bladder. Injuries to the spinal cord can also interrupt the signals to the nerves that control the bladder.

Sexually transmitted diseases can cause UAB. They include AIDS, herpes, and neurosyphilis, or tabes dorsalis. Neurosyphilis occurs when the bacteria that causes syphilis attacks the central nervous system. People who develop neurosyphilis have had untreated syphilis for a long time.

Diagnosis & Tests

The physician performs a physical examination on the patient to diagnose underactive bladder syndrome, and order urodynamic testing which measures how well the bladder functions. A urodynamic test measures the pressure inside the bladder, how much urine it can hold and the flow rate of the urine. Sensors may be attached to the area around the patient's urethra or rectum during the tests.

The doctor may perform a cystoscopy. During this procedure, the doctor inserts a cystoscope into the urethra and then into the bladder to examine it. The doctor may order X-rays, computed tomography (CT) scans, or magnetic resonance imaging (MRI)s to try to find the cause of the underactive bladder.

Treatment & Therapy

It's possible for UAB to be treated without drugs. Losing weight and avoiding foods that stimulate the bladder help with many patients. Foods to avoid include alcohol and beverages with caffeine in them.

Patients have been helped by going to the bathroom on a schedule instead of when they feel the urge to go. The patient may also double void when they use the toilet. This means they urinate, wait a few minutes, then try to urinate again.

The doctor may recommend that the patient keep a diary. A diary helps to pinpoint situations that either ease the UAB or make it worse.

Some drugs help with underactive bladder, though medical experts don't believe drugs are the best treatment. Two drugs used to treat the condition are bethanechol or distigmine. These drugs help the bladder to contract, which helps the flow of urine.

Catheters are used to help the patient void urine. They can be inserted only when the patient needs to urinate or they can be left in.

Surgery is an option in severe cases of underactive bladder. A surgeon is able to give the patient an artificial sphincter muscle if their own urinary sphincter muscle isn't working. The artificial sphincter is placed around the urethra and operated by a pump placed beneath the patient's skin.

The surgeon can create a stoma, or opening in the patient's abdomen. Urine passes through the stoma and collects in a pouch. Other treatments include using part of the patient's colon to increase the size of the bladder and injections of Botox into the bladder.

Prevention & Prophylaxis

Preventing diseases such as diabetes can reduce the risk of developing an underactive bladder. Maintaining a healthy weight and avoiding foods that irritate the bladder help to prevent and/or alleviate symptoms of the condition in many patients.