Cat Diarrhea: Causes, Diagnosis, and Treatment

Cat diarrhea is a very common presenting complaint among cats brought into my office for examination. In general, it is one of the most frequent reasons cats are taken to see the veterinarian.

Diarrhea occurs in kittens, adult cats, geriatrics, males and females and all breeds. It has many different causes, almost too many to list.

Free Pocket Vet App

Can your cat have diarrhea that is of no consequence? Absolutely. They can have an upset GI tract for a day just like we can. However, it is important for any cat with diarrhea that lasts more than a day to have a physical exam and microscopic evaluation of the stool.

Cats can quickly become dehydrated due to their small size. Also, since there are so many causes of feline diarrhea, it is very important to diagnose the right cause so that treatment can be appropriate.

You can hear more about cat diarrhea on our radio show:

Causes of Diarrhea in Cats

What are some of the causes of diarrhea in cats? There are many and they can include feline allergies, specifically food allergies, intestinal parasites, feline inflammatory bowel disease, hyperthyroidism, diabetes, ingestion of a poison, feline leukemia, several different viruses, and much more.

Constipation can even be confused for cat diarrhea. When a cat is constipated, they often strain in an effort to move the stool along and in the process, some liquid stool may ooze around the hard, impacted feces and be the only thing the cat produces. The owner then mistakenly believes their cat has diarrhea when, in fact, the cat is constipated. I have seen many cats in my hospital that were brought in with an owner diagnosis of diarrhea when they actually turned out to be constipated.

Here's How YOU Can Directly Ask Your Questions!



Fluids may be needed for dehydration when a cat has diarrhea and cat medication may be needed. Without proper diagnostics, it is not possible to administer the correct treatment. That is not safe or fair for the cat or the owner.

Also, a major word of warning: Don't forget, feline medication can be very different from human or even dog medication and dosages are certainly different. Don't ever give your cat a medication for human diarrhea without checking with your veterinarian. You can kill your cat doing that.

cat in litter box
Pin It

Diarrhea can be difficult to treat, but almost never impossible. Sometimes it requires enormous patience on the part of the owner and a firm trust in the veterinarian because it may take time and require several stages of diagnostics and even trials of treatment to cure diarrhea.

Diagnosing the Cause of Your Cat's Diarrhea

I have seen far too many cat owners run from one vet to another if the diarrhea is not resolved with one visit. That is unfortunate because diarrhea in a cat is one of those conditions that may take a few days to a few weeks to diagnose and treat. Running from vet to vet is a waste of precious time unless you have good reason to doubt the competency of your veterinarian.

Diagnostics include at a minimum a thorough history, complete physical exam, and a fecal analysis. In addition, blood work may be necessary and possibly xrays. In extreme cases, intestinal biopsies may be needed.

Treating Cat Diarrhea

Treatment can range from something as mild as withholding food for 24 hours to a change in diet to medication. Again, the treatment for food allergy is very different from the treatment for intestinal parasites which is very different from inflammatory bowel disease. Therefore, it is critical that a proper diagnosis be made so the right treatment can be chosen.

Below, you will find questions from readers and my answers which are full of valuable information on cat diarrhea.


Read Dr. Neely's Response to Dozens of Questions
About A Colorless Fluid Leaking From Cats Rear Ends


Return from Cat Diarrhea to the Symptoms of Cat Illnesses

Return to the Ask The Cat Doctor Home page

What Other Cat Lovers Have Said About Cat Diarrhea

Click below to see contributions from other visitors to this page...

Diarrhea in Purebred Kitten 
Dear Dr,We have a purebreed kitten that we just got. He is 4 months old now. The breeder is an excellent breeder that loves and cares for her little …

Sick Kitty with Loose Feces 
QUESTION: My vet says my cat has an intestinal parasite and we are now on our second medication to try and clear it up. Her symptoms are: increased …

Cat Leaking Feces 
QUESTION: My female cat who is 14 years old has been leaking feces all over the house. It is not solid but just a small amount of liquid. Outside …

Loose Stool in a Cat 
QUESTION: My cat has had loose stool for almost 3 years. I have been to the vet numerous times. They can't find anything, but keep telling me that …

Sick Cat With Bloody Diarrhea 
QUESTION My cat seems to have bloody diarrhea. The problem is I cant afford to take him to the vet. I know this isn't normal but I'm curious …

Munchkin cat with chronic loose stool 
Hello Dr. Neely. Thank you for taking the time to read this. I searched your site and could not find any question quite like mine.I recently adopted …

Diarrhea in cat 
Hi there, my cat is fairly old but at the same time he looks and acts like he is young (13 years) and is active, runs, jumps. etc. He had a surgery …

Nursing cat has diarrhea 
My cat gave birth to 3 kittens 18 days ago. She has had diarrhea today, yesterday, and for two days before that.This is a very young cat that showed …

Cat discharge, sleepy, diarrhea, very worried 
Our 3 year old male cat has slept for two days and has diarrhea and now his bum has a discharge. He just got up to use his litter box but won't eat. …

Feline Bowel Problems 
My 17 year old cat has had a bowel problem for quite some time. He is constipated and has lactulose added to his food on a daily basis. Without this, …

Chronic Diarrhea in Kitten 
I understand that you have addressed the issue of diarrhea elsewhere, but this case is unique… We have a 5 month old kitten, who was found as a stray. …

It's not diarreha, but I'm still worried about my cats? 
Recently, my 11 year old cat, Lily, has been going outside more. While she never leaves the yard, she has gotten vocal with a couple of the neighbor's …

Cat Testicles

Enlarged, Red Testicles and Anus 
QUESTION There is an outside barn cat about a year old that has developed redness and swelling of the testicles and anus. I am pretty sure there …