Diarrhea is the passage of feces as unformed or loose stools, usually in increased volume and
frequency of passage. It is a result of increased speed of passage of fecal material (digested
food) through the intestine combined with decreased absorption of water, nutrients and
electrolytes. There are many causes of diarrhea. Diarrhea may occur as the only sign or in
combination with other signs of more widespread disease, or with symptoms that result from
prolonged or severe diarrhea.

How can I tell if my cat has diarrhea? If your normally well-trained cat suddenly starts having
accidents around the house, and the stools are unformed to fluid, then diarrhea is obvious. But
if the cat is still using the litter box and covering up its feces or defecates outdoors, it may be
difficult to initially notice diarrhea. Staining and soiling of the hair-coat around the back end in
long-haired breeds is often associated with diarrhea. It is important to remember that some
variation in the consistency of stools is not unusual. Changes in diet can lead to temporary
changes in the stool. If frequent liquid or semi-liquid stools persist for more than two days, you
should consult your veterinarian. If there are more general signs of illness in your cat, then call
your veterinarian immediately.

If you have more than one cat then it is important to try and determine if it is just one cat or if
other cats also have diarrhea.

What are some causes of diarrhea?

Diarrhea is not a disease in itself but a sign that may reflect one or more of many different
problems. Most involve some degree of inflammation of one or more sections of the alimentary
or gastro-intestinal (GI) tract. the GI tract is the continuous tube that carries food from mouth to
anus. Inflammation can be caused by infectious agents (bacteria, viruses, coccidia, intestinal
worms, etc.) or by non-infectious irritants such as chemical toxins, poisonous plants, and so on.
Allergies to certain specific components of a diet may be responsible for diarrhea. Diarrhea may
occur as a sole symptom or as one of several symptoms of a more generalized disease problem.

How is the cause determined?

It is important to provide your veterinarian with a very good medical history. Preferably write
this out in chronological order before you go to the clinic. Be as detailed as possible on the date
you first noticed a problem, even in retrospect. Also report the progression of the clinical signs.
Note any changes in the normal routine of your cat or your household. How frequent are the
stools? What is the color, consistency, and smell of the feces? Is the cat showing any other signs
such as vomiting, loss of appetite, lethargy, or loss of weight? We have a checklist to help you
put this history together.

Besides a thorough clinical exam, your veterinarian may recommend additional diagnostic tests.
These tests may be deferred in mild cases of diarrhea unless initial treatment fails or the
condition worsens. Tests may include blood work, stool and/or rectal swab samples for
parasite examination and culture, radiographs, and endoscope exam.

How is diarrhea treated?

Initially, and often in advance of in-depth work-up, a non-specific approach may be adopted. It
is a good idea to withhold food for 24 hours and encourage water consumption. Gradually re-
introduce small quantities of a light, easily digestible diet. Boiled rice or other pasta with some
boiled skinless chicken may be given if a special veterinary diet is not available. Anti-diarrheal
medication(s) may be used to help speed your pet’s recovery. Many cases of diarrhea will
respond quite readily to simple treatment, without the initial cause ever being established. As
stools return to normal, the cat’s regular diet can be gradually reintroduced, mixed initially with
the bland rice-chicken or similar diet.

If there is little or no improvement over two or three days, if the cat is not taking any water or if
the cat’s health worsens, then your veterinarian should be notified at once. Treatment may be
more aggressive based on the results of an in-depth clinical work-up as outlined above. Loss of
fluid is one of the most serious aspects of severe or prolonged diarrhea, and if vomiting is
present, dehydration can rapidly escalate. Correcting the dehydration may require intravenous
or subcutaneous fluids.

Can I use anti-diarrheals from the human pharmacy?

Some of the preparations recommended for people are very dangerous for cats so never use a
medication without consulting your veterinarian first.

My cat has chronic diarrhea. Will it get better?

Chronic diarrhea that has been present for 2-3 weeks or longer may prove more difficult to
diagnose and to treat effectively. Even extensive work-up does not always provide a definitive
answer to the problem. But in many cases a thorough clinical work-up, including food trials, can
result in a successful outcome.
This client information sheet is based on material written by Ernest E. Ward Jr., DVM.
© Copyright 2002 Lifelearn Inc. Used with permission under license. September 30, 2009.
Cambridge VetCare
Animal Clinic, PA
Cambridge, MN