Causes and Treatment of Diarrhea in Cats

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Diarrhea is usually a symptom of a bigger problem in your cat, sometimes one that is quite urgent. Learn the common causes of diarrhea in cats, treatments, and cures.

Diarrhea is usually a symptom of a bigger problem in your cat, sometimes one that is quite urgent. You will want to note that many products used to control diarrhea in humans (such as Pepto Bismol) are toxic to cats so you really need to get to the root of the problem.

Food Allergies

Cats with sensitive stomachs will often either vomit or have diarrhea. One can check the food for known problem causing ingredients, pork, beef, soy, wheat, corn, and color dyes. Eliminating problem ingredients will often see total recovery. Cat owners must become familiar with reading pet food ingredient lists. The problem might be fixed by switching to a better quality hypoallergenic food, or by cooking for the cat, starting off with just chicken (or lamb) and adding ingredients to see when problems occur.

Food that is Too Rich

Since cats are true carnivores and need a lot of meat in their diet, and most cat foods use very little meat, this is seldom a cause of diarrhea but should not be overlooked when a pet is on a super premium food. This can occur as well if a cat eats only canned food, or when an adult cat is being fed kitten food.

Sudden Food Change

More often if a cat is suddenly switched from one food to another they get a bout of diarrhea. One can remove food for a short period, such as half a day, and mix it with the cats old food, or reintroduce the new food slowly if there is no old food left.

Worms and Bacteria

Worms and bacteria generally cause diarrhea in cats. This will often be bloody diarrhea, and may not be all the time. There are many kinds of worms or bacteria a cat can get so, while people often try to treat worms with worming medications they buy a pet stores, it should be noted that those do not kill every kind of worm, so a proper diagnosis from a veterinarian (through a stool sample) will help pinpoint what kind of worm (or bacteria) is plaguing the cat, and the cat can be treated correctly.


Just like humans cats can get diarrhea as the result of stress. It is pretty hard to stress an animal that sleeps 16 hours a day, but in a hectic household, one where the cat is chased frequently, or if a new cat (dog, baby) has entered the home, the cat might be stressed.

Something they Ate

Cats are generally fussy eaters (unlike dogs) and so they seldom eat things that make them have diarrhea (they will eat grass to make themselves vomit).

kitten in the litter box

photo source

Lack of Litter Box Availability

Quite simply put, if a cat cannot find a place to do its business, and has to hold it for a while, it may have bad diarrhea by the time it can finally relieve itself. This can also be a problem when a home has more cats than litter boxes, or when a litter box is dirty.

Pregnancy or Heat

Some cats have diarrhea when their hormones change, either due to going into heat, or being pregnant. As pregnant, and nursing cats, need to be fed kitten food, this can also be a problem.

Keep in Mind

  • If your cat has diarrhea for more than one or two days, it can dehydrate, but equally important, your cat should see a veterinarian to have a proper diagnosis made (especially if it is a kitten). Do not just treat the diarrhea, find the cause and treat that!
  • Kids should not be responsible for cleaning the litter as they may not alert you to problems.
  • Never just treat a cat for diarrhea without finding out the cause.

Related Links on Cat Health

Why is my cat Not Using its Litter Box?

Shoud Cats be Fed Vegetarian or Vegan Diets?

Cat Food, Wet or Dry?

Preventing Cancer in Cats


Susan Kaul
Posted on Jul 28, 2010
Charlene Collins
Posted on Jul 26, 2010