Urinary Incontinence
This information is not meant to be a substitute for veterinary care.
Always follow the instructions provided by your veterinarian.
Urinary incontinence is the involuntary passing of urine. Pets can be
incontinent for many different reasons. Those reasons can involve the
bladder, the urethra which is the tube from the bladder to the outside,
or incontinence can be caused by abnormalities in the parts of the brain
and spinal cord that control bladder function. Related anatomy
dog/
cat
Incontinence can be confused with diseases that cause a pet to
urinate frequently. This pet health topic only discusses incontinence,
not frequent urination.
Incontinence can also be confused with submissive urination. Submissive
urination occurs when a dog is acting submissive to a person or to
another dog. Submissive urination occurs more frequently in young
animals. The dog usually rolls on its back and urinates. These dogs can
also urinate normally.
Young animals may have a birth defect causing incontinence. The most
common birth defect that causes incontinence in young dogs is ectopic ureter(s).
The ureters carry urine from the kidneys to the bladder. If one or both ureters
by-pass the bladder and connect to an abnormal location such as the urethra or
vagina, the puppy may drip urine. Siberian Huskies are most often affected.
Other breeds that have a higher occurrence of this birth defect include:
- Miniature Poodle
- Labrador Retriever
- Collie
- Welsh Corgi
- Wire-haired Fox Terrier
- West Highland White Terrier
Female dogs are more commonly affected. If only one ureter is abnormal
the dog will dribble urine but can also urinate normally. If both
ureters are affected then the puppy will only dribble urine and cannot
pass urine normally.
To diagnose this condition a dye study of the bladder is usually
performed. Sometimes the abnormal opening into the vagina can be seen
during a careful examination under anesthesia using special equipment.
Most puppies with ectopic ureter(s) also have a bladder infection that
will improve with antibiotics but the infection will return until the
problem is corrected.
In some cases the ureter can be surgically moved back to the normal
location in the bladder and incontinence may resolve. In other cases,
long standing infection of the kidney may have damaged the kidney
requiring the removal of one kidney. In yet other cases the abnormality
of the ureter can be corrected but the pet remains incontinent, probably
due to the presence of other birth defects in the urinary system.
A bladder infection can cause either a strong urge to urinate or if the
bladder infection is long standing it can cause scarring of the bladder
preventing it from stretching to hold urine. In this case the pet is usually not
truly incontinent in that
they know they are urinating, but they have such a strong
urge to empty their bladder that they may urinate in abnormal locations or
urinate very frequently. It is common to evaluate incontinent pets for the
presence of a bladder infection.
Pets with a partial blockage of the urethra with a stone or a tumor may
show incontinence. If they cannot empty their bladder completely because
something is blocking the path to the outside, the bladder may get so large that
the back pressure of urine in the bladder actually forces some urine to leak
around the blockage. In these pets the enlarged bladder can be felt on
examination. Total blockage of urine flow is usually fatal in 3 to 4 days.
Hormone-responsive incontinence occurs in neutered dogs of both sexes and
occasionally in spayed female cats but occurs most commonly in female dogs. The
pet can urinate normally, but they leak urine while resting. Physical
examination and blood and urine tests are usually normal in these pets.
Hormone-responsive incontinence can occur months to years after a pet is
neutered.
As pets age they may become incontinent. This may be due to a weakening of
the muscles that hold urine in the bladder. There are many diseases that can
cause a pet to create more urine than normal (polyuria) and several of these
occur in older pets. If a pet has one of these diseases and often has a full
bladder, the full bladder can push against the weakened sphincter and cause
incontinence. Older pets can also develop senility and simply be unaware that
they are dribbling urine.
Dogs and cats with brain or spinal cord disease may either dribble urine or
be unable to pass urine. Most often they will have other signs of nervous system
disease such as muscle weakness or paralysis.
Intermittent incontinence, primarily at rest, has been reported in cats of
both sexes that are positive for the feline leukemia virus. How the virus causes
incontinence is unknown.
A less common cause of incontinence in female dogs is called vulvovaginal
stenosis. It is a condition in which the vagina at the level where the urethra
ends is narrowed. Occasionally when the pet urinates, some urine will get
trapped in the vagina in front of this narrowed area. Then when they rise after
lying down the urine pours out. This condition can be diagnosed by feeling the
vagina with a gloved finger. In some dogs the narrowing can be stretched under
anesthesia. The incontinence may or may not resolve as sometimes other defects
are also present.
Diagnosis of incontinence
The tests performed to evaluate a pet with incontinence depend upon the
age of the pet and on the presence or absence of other signs. It is
common to collect a urine sample for bacterial culture and to see if the
urine is dilute or shows evidence of an infection. Infections of the
urine may be secondary to another cause of incontinence.
Questions that your veterinarian will ask to help identify the cause of
your pet’s problem include:
- The age when incontinence first appeared
- When the incontinence is usually observed, for example at rest or
with activity
- Whether the pet can urinate normally
- Previous surgeries (such as neutering) and illness
- Use of medications that might cause the urine to be dilute such as
diuretics, anticonvulsants or prednisone
- How much water the pet drinks
- How frequently the pet urinates and whether the pet seems to be
uncomfortable when he or she urinates
- Whether the pet shows any signs of nervous system disease such as
weakness or seizures
Blood tests may be performed to look for evidence of kidney damage from
infection or for the presence of diseases that might lead to increased
urine production.
Plain and/or dye X-rays or ultrasound may be performed to look at the
parts of the urinary tract.
Treating the incontinent patient
Specific treatment of an underlying disease may resolve incontinence;
for example, surgery to correct an ectopic ureter. Inappropriate
urination caused by behavioral problems may be corrected with training
that modifies the pet’s behavior.
When no specific cause can be identified for the incontinence drugs may be
given that increase the tone of the muscles that hold urine in the
bladder. Some drugs that are used for this purpose include estrogen,
ephedrine and phenylpropanolamine.
Drug therapy for incontinence may be based on “trial” of different
drugs in various doses. Since some of these drugs can have side effects
so low doses are tried first. Some drugs may be slow to have an effect
so as long as there are no undesirable side effects, a drug trial should
continue for several weeks before the drug is considered not to be
effective.
Washington State University assumes no liability for injury to you
or your pet incurred by following these descriptions or procedures.
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