Diarrhea in Cats 101

Just like people, most instances of mild diarrhea resolve if given a little time. If your cat has frequent, profuse, or bloody diarrhea, or other symptoms such as vomiting, painful belly, and/or abnormal behavior, it’s time to call a vet right away.

Common Causes of Diarrhea in Cats

1. Sudden Change of Diet

A new diet should be introduced gradually. A sudden switch can cause diarrhea by upsetting the gut microbiome (healthy bacteria that live in the digestive system and aid digestion). This is particularly important when you bring a new kitten or cat home for the first time. The combination of a little stress and an abrupt change in diet will easily trigger diarrhea.

When rehoming a cat or kitten, always ensure you feed them what they’re already eating and if you wish to change over their food, wait a few weeks, then make the transition slowly over 5-7 days. Introduce tiny amounts of new food on day 1 and increase this amount while decreasing the other food over the remaining days. You can reduce stress levels by using a pheromone diffuser.

2. Dietary Indiscretion

Dietary indiscretion refers to your cat eating things he shouldn’t. Some cats may go through the trash or even come across a dead carcass of interest. Some cats will have the sense to leave them alone, but unfortunately, not all. The ingested waste can cause diarrhea in a variety of ways:

Toxins - These range from mild to serious toxins and therefore cause a range of different symptoms, but diarrhea is a common one. If there are more serious signs of toxicity such as vomiting, lethargy, incoordination, or lack of responsiveness, help should be sought immediately.

Mechanical effect of indigestible food - This can act like sandpaper on the lining of the bowels, causing irritation. In some cases, this can cause blood in the stool (See our articleon bloody diarrhea). Typically, we think of dogs eating things they shouldn’t but it should be noted that some cats do too. This is important because though uncommon, indigestible material can become lodged, obstructing the intestines. A partial obstruction can cause diarrhea but is a very serious condition that may need to be treated surgically. Keep an eye on your kitty to make sure they aren’t inclined to eat things they shouldn’t and always let your vet know if you suspect they have.

Ingestion of harmful bacteria (E.coli, Salmonella, etc.) - These are true cases of “food poisoning” and some of these nasty bugs could be transmitted to humans. It should be noted that it’s preferable to practice good hygiene, including wearing gloves and extensive handwashing if you need to clean up your pet’s diarrhea.

3. Hairballs

Hairballs in cats are very common. They normally cause constipation; however, this occasionally looks like diarrhea as they strain to pass very small amounts of liquid. Cats that are prone to hairballs are often, but not always, long-haired. There are special diets or supplements that are made for cats that suffer from them.

For more information, check out our article on hairballs in cats!

4. Dietary Intolerance/Food Allergy

Most food allergies are intolerances that can be caused by any part of the diet. For example, the protein or carbohydrate source. Some pet foods are rich in additives, flavorings, and preservatives, and some foods can have inconsistent manufacturing processes. These make certain foods more likely to cause a reaction.

The best foods for a cat with suspected dietary sensitivities should be discussed with your vet, as they are often only available by prescription. Beware that the term “hypoallergenic” when referring to pet food is not regulated and therefore the food may not be as helpful as hoped.

5. Parasites

Many parasites can cause diarrhea, especially in kittens. Examples include giardia, coccidia, and roundworms. Most vets recommend regular deworming and a yearly fecal exam as part of an annual checkup. These intestinal parasites are usually passed from cat-to-cat or picked up from the environment. Some cats can re-infect themselves even after treatment, which is why it’s important to keep litter boxes very clean.

6. Viral Infections

Usually passed from cat-to-cat, these include serious infections such as feline panleukopaenia virus that can occur in unvaccinated kittens. Less serious viruses such as rotavirus also cause milder versions of diarrhea in kittens.

Keep reading here to learn about preventative vaccination in kittens!

7. Prescribed Medications

Prescription drugs such as anti-inflammatories or antibiotics can cause diarrhea in cats. A vet must be consulted before deciding to continue or discard the medication.

8. Other Causes of Diarrhea in Cats

Diarrhea may be caused by certain types of metabolic disease and liver disease. Certain cats can be prone to Inflammatory Bowel Disease (IBD). These diseases are likely to produce ongoing signs and not respond to the usual therapies, so diarrhea that doesn’t resolve within a reasonable timeframe should always be investigated further by your vet.

Why is it important to treat my cat for diarrhea?

Diarrhea can lead to dehydration so your cat must continue to drink plenty of water. Offer a bland diet that is easily absorbed and digested in the intestinal tract. Diarrhea that doesn’t resolve must be investigated. For everyone involved, a swift recovery from diarrhea is preferred! Consulting a vet ensures the most effective treatment plan is made for your cat.

What about giving my cat over-the-counter medication for diarrhea?

Do not give any over the counter (OTC) medications to your cat without talking to your vet first. Not only can OTC medications be dangerous for pets, but they can also hide an underlying problem.

Home Remedies for Your Cat’s Diarrhea

If your vet suspects that your cat’s diarrhea isn’t any more serious than a case of dietary indiscretion or isolated food intolerance then they may suggest remedies available at home, particularly if you’re unable to schedule an appointment or visit the clinic that day.

1. Withhold Food for 24 Hours

Home remedies for diarrhea often start with a food fast - skipping one meal is recommended, with a maximum of 12 hours between meals. This gives the digestive system a break and time to heal. But you should always provide easy access to fresh water. Your pet will likely need to drink more than usual. Please note, this recommendation is NOT appropriate for small kittens. Do not withhold food from your kitten if she has diarrhea.

2. Offer Bland Food

After the fast, reintroduce bland food in small quantities. Homemade examples of bland food are boiled white rice mixed with equal amounts of white meat such as chicken or fish. The meat should be baked, steamed, or microwaved, with no added fat. Offer each meal in small quantities (ie. one tablespoon). This can be offered every 3-4 hours.

Proprietary brands of hypoallergenic food for digestive upsets exist for this purpose and are superior to homemade food due to a precise and tailored mix of nutrients. Some of these foods also include a pre/probiotic. The author always keeps a few cans of this in the pantry in case diarrhea strikes!

Feed the bland diet for at least 48 hours after a normal stool has formed. This may take several days so it’s ideal to purchase one of these formulated diets to ensure that your cat receives appropriate vitamins and minerals. Properly formulated diets become very important if your cat has diarrhea for a longer period.

For more feeding instructions and recipes, follow this link!

3. Probiotics

Probiotics have been proven to speed diarrhea recovery times. The studies looking at this used a proprietary blend of probiotics for cats. However, if you can’t get your hands on that right away you can try some natural yogurt. A teaspoon is plenty for cats.

4. Electrolyte Solutions

Electrolyte solutions are not essential for mild bouts of diarrhea and they aren’t easy to make at home. Generally, if the diarrhea is severe enough to cause electrolyte imbalances then it’s time to see the vet. However, adding a very small amount of salt-free meat broth to your cat’s water may encourage him to drink.

If the diarrhea persists for more than 24 hours, or more serious signs develop at any stage (such as vomiting, lethargy, or weakness) then veterinary care should be sought immediately.

What to Do if Your Kitten Has Diarrhea

It’s important to speak to a vet as soon as possible if your kitten has diarrhea. Your vet will likely run a test on a fresh stool sample to screen for parasites. Parasites such as giardia and coccidia are very common causes of diarrhea in young kittens. In certain pedigree breeds such as Bengals, a parasite called Tritrichomonas Foetus can be involved.

Your vet will request further information about the health of your kitten, specifically whether she is vaccinated for diseases such as panleukopenia. Although this is uncommon, it causes a high mortality rate. The diarrhea is usually profuse, and the kitten may have other signs of disease.

Other things to consider include a recent change in diet, environment, or addition of treats to encourage good behaviors. These are much more common causes of diarrhea in kittens. The symptoms are mild and usually, your kitten will appear well and happy if these are the cause.

Your vet will be able to determine whether your kitten needs further diagnostics or if some simple remedies can be tried at home.

Home Remedies for Kitten Diarrhea

Home remedy options need to be modified for kittens. Generally, young kittens are fed 3-4 times per day and/or graze on kibble throughout the day. You could skip one meal or withdraw the kibble for a maximum of 5 hours to rest the digestive system. A 24-hour fast is too long for a kitten and should never be attempted. Reintroducing bland food is a good idea: 1 tablespoon of chicken/rice mixture (see above) can be offered approximately every 2-3 hours.

Kittens recover quickly but can also deteriorate quickly. Keep a close eye on their energy levels and appetite. Never hesitate to contact your vet again if you have concerns about your pet’s recovery.

Tips for Cleaning Up Diarrhea

Wear gloves and use a good disinfectant to clean the litterbox or any other areas.

• Try to wash your cat’s bottom if it has become soiled. Using an antibacterial soap such as Dial is okay if you don’t have an antibacterial dog/cat shampoo.
• If you can, collect a sample of stool. It’s likely your vet will want to test it for common parasites.
• Be cautious if you have other cats or children. Occasionally diarrhea will be caused by an infection that can be passed on to others. Practice strict hygiene and keep them separated if possible.

My cat’s diarrhea isn’t getting better. When should I take him to the vet?

If your cat is experiencing any of these symptoms, it's time to schedule a vet appointment:

• The diarrhea is bloody or very dark/black
• Your cat is becoming lethargic or weak
• Your cat won’t eat food for more than 24 hours or your kitten misses more than one meal.
• Your cat is dehydrated (check for dry sticky gums or skin tent time)
• You are aware of an object that may have been swallowed that could block the stomach or intestines
• Your kitten has stomach pain or a swollen abdomen
• There has been no response to home care for 3 days or for young kittens, 1 day
• Your cat has multiple episodes of vomiting and/or diarrhea in a short period of time

How will the vet treat my cat’s diarrhea?

If your cat is very sick or dehydrated, he may need to stay in the hospital.

• Your cat may be given IV fluids to correct dehydration and replace lost electrolytes (sodium, potassium, chloride).
• Blood work may be done to check red and white blood cell counts, as well as evaluate internal organ function (liver, kidneys, pancreas).
• Other diagnostics might be recommended to determine the cause of your cat’s diarrhea. These include x-rays or ultrasound of the abdomen, fecal exam, and tests for diseases like pancreatitis or panleukopenia.

Treatments for diarrhea and any underlying issues will likely continue once your cat is discharged to go home:

• A bland diet that requires minimal digestion will likely be prescribed.
• Your cat may go home with prescriptions for anti-nausea medication, antacids, pain relief, and probiotics to replace normal gut bacteria.

Read more:

Your Complete Guide to Vomiting in Cats

Food Allergies in Dogs and Cats

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