National Kidney and Urologic Diseases Information Clearinghouse
For the urinary system to do its job, muscles and nerves must work together to hold
urine in the bladder and then release it at the right time. Nerves carry messages from
NATIONAL
the bladder to the brain to let it know when
INSTITUTES
the bladder is full. They also carry messages
OF HEALTH
from the brain to the bladder, telling muscles
either to tighten or release. A nerve prob
lem might affect your bladder control if the nerves that are supposed to carry messages
between the brain and the bladder do not work properly.
U.S. Department of Health and Human Services What bladder control problems does nerve damage cause? Nerves that work poorly can lead to three
different kinds of bladder control problems.
Overactive bladder. Damaged nerves may
send signals to the bladder at the wrong time, causing its muscles to squeeze with
Nerves carry signals from the brain to the bladder
• urinary frequency—defined as urination
nerves to the sphincter muscles are dam
aged, the muscles may become loose and allow leakage or stay tight when you are
• urinary urgency—the sudden, strong
Urine retention. For some people, nerve • urge incontinence—leakage of urine
not get the message that it is time to release
urine or are too weak to completely empty
Poor control of sphincter muscles. Sphinc
ter muscles surround the urethra and keep
full, urine may back up and the increasing
it closed to hold urine in the bladder. If the
pressure may damage the kidneys. Or urine
that stays too long may lead to an infection in
If nerve damage is suspected, the doctor
the kidneys or bladder. Urine retention may
may need to test both the bladder itself and
the nervous system, including the brain. Three different kinds of tests might be used:
What causes nerve damage? Urodynamics. These tests involve measur
ing pressure in the bladder while it is being
filled to see how much it can hold and then
checking to see whether the bladder empties completely and effi ciently.
Imaging. The doctor may use different types
• infections of the brain or spinal cord
of equipment—x rays, magnetic resonance
imaging (MRI), and computerized tomography (CT) scans—to take pictures of the
urinary tract and nervous system, including
EEG and EMG. An electroencephalograph
(EEG) is a test in which wires with pads are
placed on the forehead to sense any dysfunction in the brain. The doctor may also use an
In addition, some children are born with
nerve problems that can keep the bladder
with pads placed on the lower abdomen to
from releasing urine, leading to urinary
test the nerves and muscles of the bladder.
What are the treatments for How will the doctor test for overactive bladder? nerve damage and bladder
The treatment for a bladder control problem
control problems?
depends on the cause of the nerve damage
Any evaluation for a health problem begins
and the type of voiding dysfunction that
with a medical history and a general physical
examination. Your doctor can use this infor
In the case of overactive bladder, your doctor
mation to narrow down the possible causes
may suggest a number of strategies, including
bladder training, electrical stimulation, drug therapy, and, in severe cases where all other treatments have failed, surgery.
Bladder training. Your doctor may ask you to keep a bladder diary—a record of your fluid intake, trips to the bathroom, and episodes of urine leakage. This record may indicate a pattern and suggest ways to
avoid accidents by making a point of using
the bathroom at certain times of the day—a practice called timed voiding. As you gain
control, you can extend the time between trips to the bathroom. Bladder training also includes Kegel exercises to strengthen the muscles that hold in urine.
Electrical stimulation. Mild electrical pulses
can be used to stimulate the nerves that control the bladder and sphincter muscles. Depending on which nerves the doctor plans
A device can be placed under your skin to deliver
to treat, these pulses can be given through
mild electrical pulses to the nerves that control bladder function.
the vagina or anus, or by using patches on the skin. Another method is a minor surgical procedure to place the electric wire near
Drug therapy. Different drugs can affect the
the tailbone. This procedure involves two
nerves and muscles of the urinary tract in
steps. First, the wire is placed under the skin
and connected to a temporary stimulator,
• Drugs that relax bladder muscles and
which you carry with you for several days.
If your condition improves during this trial
period, then the wire is placed next to the
tailbone and attached to a permanent stimu
lator under your skin. The Food and Drug
which belong to the class of drugs called
device, marketed as the InterStim system, to
side effect is dry mouth, although large
treat urge incontinence, urgency-frequency
syndrome, and urinary retention in patients
stipation, a faster heartbeat, and fl ush
for whom other treatments have not worked.
ing. A new patch delivery system for oxybutynin (Oxytrol) may decrease side effects. Ditropan XL and Detrol LA are timed-release formulations that deliver a low level of the drug continuously in the body. These drugs have the advantage of once-a-day administration. In 2004, the FDA approved trospium chloride (Sanctura), darifenacin (Enablex), and solifenacin succinate (VESIcare) for the treatment of overactive bladder.
• Drugs for depression that also relax
Try not to squeeze other muscles at the same
time. Be careful not to tighten your stom
ach, legs, or buttocks. Squeezing the wrong
antidepressant. Side effects may include
muscles can put more pressure on your blad
der control muscles. Just squeeze the pelvic
Additional drugs are being evaluated for the
At fi rst, find a quiet spot to practice—your
bathroom or bedroom—so you can concen
trate. Pull in the pelvic muscles and hold for a count of 3. Then relax for a count of
Surgery. In extreme cases, when incontinence
3. Repeat, but don’t overdo it. Work up to
is severe and other treatments have failed,
3 sets of 10 repeats. Start doing your pelvic
surgery may be considered. The bladder may
muscle exercises lying down. This position is
be made larger through an operation known
the easiest because the muscles do not need
as augmentation cystoplasty, in which a part
to work against gravity. When your muscles
of the diseased bladder is replaced with a
get stronger, do your exercises sitting or
section taken from the patient’s bowel. This
standing. Working against gravity is like
operation may improve the ability to store
urine but may make the bladder more diffi cult to empty, making regular catheterization
Be patient. Don’t give up. It takes just
necessary. Additional risks of surgery include
5 minutes a day. You may not feel your blad
the bladder breaking open and leaking urine
der control improve for 3 to 6 weeks. Still,
into the body, bladder stones, mucus in the
most people do notice an improvement after
Some people with nerve damage cannot tell
How do you do Kegel
whether they are doing Kegel exercises cor
exercises?
rectly. If you are not sure, ask your doctor
Kegel exercises strengthen the muscles that
or nurse to examine you while you try to
do them. If you are not squeezing the right muscles, you can still learn proper Kegel
The first step in doing Kegel exercises is
exercises by doing special training with bio
to find the right muscles. Imagine you are
feedback, electrical stimulation, or both.
trying to stop yourself from passing gas. Squeeze the muscles you would use. If you sense a “pulling” feeling, those are the right muscles for pelvic exercises.
What are the treatments for Botox injection. Botulinum toxin type A lack of coordination between (Botox) is best known as a cosmetic treatment
for facial wrinkles. Doctors have also found
the bladder and urethra?
that botulinum toxin is useful in blocking
The job of the sphincter muscles is to hold
spasms like eye ticks or relaxing muscles in
urine in the bladder by squeezing the urethra
patients with multiple sclerosis. Urologists
shut. If the urethral sphincter fails to stay
have found that injecting botulinum toxin into
closed, urine may leak out of the bladder.
the tissue surrounding the sphincter can help
When nerve signals are coordinated properly,
it to relax. Although the FDA has approved
the sphincter muscles relax to allow urine
botulinum toxin only for facial cosmetic
to pass through the urethra as the bladder
purposes, researchers are studying the safety
contracts to push out urine. If the signals are
and effectiveness of botulinum toxin injection
not coordinated, the bladder and the sphinc
into the sphincter for possible FDA approval
ter may contract at the same time, so urine
Drug therapy for an uncoordinated bladder What are the treatments for and urethra. Scientists have not yet found urine retention?
a drug that works selectively on the urethral
Urine retention may occur either because
sphincter muscles, but drugs used to reduce
the bladder wall muscles cannot contract or
because the sphincter muscles cannot relax.
used to help the sphincter relax. Baclofen (Lioresal) is prescribed for muscle spasms or
Catheter. A catheter is a thin tube that can be
cramping in patients with multiple sclerosis
inserted through the urethra into the bladder
and spinal injuries. Diazepam (Valium) can
to allow urine to flow into a collection bag. If
be taken as a muscle relaxant or to reduce
you are able to place the catheter yourself,
you can learn to carry out the procedure at
blockers can also be used to relax the sphinc
regular intervals, a practice called clean inter
ter. Examples of these drugs are alfuzosin
mittent catheterization. Some patients cannot
(UroXatral), tamsulosin (Flomax), terazosin
(Hytrin), and doxazosin (Cardura). The main
damage affects their hand coordination as
side effects are low blood pressure, dizziness,
well as their voiding function. These patients
fainting, and nasal congestion. All of these
need to have a caregiver place the catheter for
drugs have been used to relax the urethral
them at regular intervals. If regular catheter
sphincter in people whose sphincter does not
placement is not feasible, the patients may
need to have an indwelling catheter that can be changed less often. Indwelling catheters have several risks, including infection, bladder stones, and bladder tumors. However, if the bladder cannot be emptied any other way, then the catheter is the only way to stop the buildup of urine in the bladder that can damage the kidneys.
Urethral stent. Stents are small tube-like Hope through Research
devices inserted into the urethra and allowed
to expand, like a spring, widening the open
ing for urine to flow out. Stents can help
has many research programs aimed at fi nding
prevent urine backup when the bladder wall
treatments for urinary disorders, including
bladder control problems caused by nerve
because of improper nerve signals. However,
stents can cause problems if they move or
have narrowed the search for a gene that
causes neurological problems in bladder,
Surgery. Men may consider a surgery that
bowel, and facial muscles. Finding the gene
removes the external sphincter—a sphinc
may lead to greater understanding of how
terotomy—or a piece of it—a sphincter
nerves and muscles work together and how
resection—to prevent urinary retention.
nerve damage can cause urination problems.
The National Institute of Child Health and
through the urethra to deliver electrical or
laser energy that burns away sphincter tissue.
orative Urological Research in Spinal Cord
Possible complications include bleeding that
Injury, a program devoted to fi nding novel
requires a transfusion and, rarely, problems
strategies to treat bladder control problems
with erections. This procedure causes loss
of urine control and requires the patient to collect urine by wearing an external catheter that fits over the penis like a condom. No external collection device is available for women.
Urinary diversion. If other treatments fail and urine regularly backs up and damages the kidneys, the doctor may recommend a urinary diversion, a procedure that may require an outside collection bag attached to a stoma, a surgically created opening where urine passes out of the body. Another form of urinary diversion replaces the bladder with a continent urinary reservoir, an internal pouch made from sections of the bowel or other tissue. This method allows the person to store urine inside the body until a catheter is used to empty it through a stoma. For More Information American Urological Association Foundation 1000 Corporate Boulevard Linthicum, MD 21090 Phone: 1–866–RING–AUA (746–4282) or
Email: patienteducation@auafoundation.org Internet: www.auafoundation.org
National Association for Continence P.O. Box 1019 Charleston, SC 29402–1019 Phone: 1–800–BLADDER (252–3337) or
Email: memberservices@nafc.org Internet: www.nafc.org
You may also find additional information about this
National Kidney and
topic by visiting MedlinePlus at www.medlineplus.gov. Urologic Diseases
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