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Will My Cat Get Diarrhea After Changing Food? What You Need To Know!

There are many reasons you might decide to change your cat’s food. Maybe your vet recommends a special diet to address your kitty’s health, or your pet store has stopped carrying your cat’s favorite food.

Unfortunately, you can’t suddenly stop feeding your cat one food brand and move on seamlessly to the next. There must be a slow and controlled introduction process to avoid tummy upset and diarrhea.

Diet change-related diarrhea doesn’t have to be a side effect of changing your cat’s diet. Keep reading to learn more about diarrhea and how to properly switch your pet to a new food.

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What Is Diarrhea?

cat having diarrhea
Image Credit: Suharji Esha, Shutterstock

Diarrhea refers to loose or unformed bowel movements with an increased amount and frequency. It happens because the fecal matter is moving fast through your cat’s digestive system and your kitty’s system isn’t about to absorb water, nutrients, and electrolytes as it should.

Diarrhea is not a disease, but it’s a clinical sign of many different diseases. Most of these conditions involve inflammation in the gastrointestinal tract. Bacteria, viruses, and intestinal worms can cause inflammation and diarrhea, as can chemical toxins and exposure to poisonous plants. Of course, food intolerances and sudden changes in diet can also cause diarrhea.


Why Do Diet Changes Cause Diarrhea?

When your cat has been eating the same food for months or even years, their digestive tract adapts to this food. So, adverse side effects may occur if there are any sudden changes to the diet it is accustomed to. The new food can alter your cat’s intestinal environment, leading to gastrointestinal issues. Vomiting and diarrhea are the most common signs that you’ve upset your kitty’s digestive system after a sudden diet change.

Your cat may also refuse to eat altogether. This is called neophobia and occurs when your pet is reluctant to try new food. Some believe that neophobia is a behavior cats engage in to protect themselves from ingesting toxic or tainted food.


How to Properly Change Your Cat’s Diet

Transitioning your cat to a new food should be a multi-day process. It’s not complicated, but there is a right and wrong way to introduce new food.

Let's look at some pointers.
  • Add a small amount of the new food in with the old. On day one of your transition, put a small portion of your cat’s new food in with its old food at mealtime.
  • Watch for signs of gastrointestinal upset. Monitor your cat closely during the transition process for any signs of gastrointestinal upset. You should also take note of how much your kitty is eating. Fussy cats may take longer to adapt to a new food, so the transition will take longer.
  • Add more new food to the old. Once you see how your kitty reacts to the new food, you can slowly increase your feeding portions. By days three or four of the transition, you should feed around 50/50 new and old food. Expect the process to take around a week at minimum, but it could take much longer, depending on your kitty.
  • Be patient. Avoid temptations to rush your kitty into this new food. Instead, let your kitty guide the speed of the transition and toss out all your ideas of how long the process should take.
  • Do not force it. It’s natural for your cat to be weary about its new diet, so don’t force it. You should never starve your pet into eating a new diet. Cats are at risk of hepatic lipidosis1, and a sudden cutback in caloric intake can be a trigger for this condition.


When Should I Take My Cat to The Vet?

Veterinarian doctor holds cat
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If you’ve transitioned to the new food as slowly as possible and your kitty is still experiencing diarrhea, it may be something other than its food causing the problem. If your kitty has diarrhea and other signs, an underlying health issue could be the culprit.

Symptoms to be on the lookout for include:
  • Vomiting
  • Lethargy
  • Bloody diarrhea
  • Not eating
  • Not drinking

A visit to the vet is in order to get your pet evaluated to see what the issue could be.

Also, if your cat refuses to eat and doesn’t take in calories for even just one day, you must get it to the vet as soon as possible. A few days of little food and inadequate daily calories can cause your kitty’s body to send fat cells to its liver to convert to energy. Cat’s bodies are not designed to metabolize fat efficiently, and their livers can then start to fail.


How Can I Clean Diarrhea?

Diarrhea is one of those pet messes that can be a real pain. Firmer poops are easy to pick up with a paper towel and buff out of the carpet with a stiff-bristled brush. Liquidy messes like diarrhea are a whole different ball game.

Clean up as much as you can with paper towels. Next, scrub the area with detergent and water. Rinse it, then blot it dry. You’ll need to use a neutralizing product, such as an enzymatic cleaner, to remove the smell and stain.

If you've got a cat, you know that even the tidiest of felines still leaves you cleaning up vomit, hair, smells, stains, and more. The Hepper Advanced Bio-Enzyme Pet Stain & Odor Eliminator Spray is the best addition to your kitty clean-up routine. Click here to learn more about this amazing product (and how it removes even the very worst smells and stains).

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Not all cats will get diarrhea when transitioning to a new food. It is not a side effect you should expect to encounter during the process, but know that if it does happen, you may need to scale back a bit. Take your time introducing new food to your kitty to reduce the likelihood of any gastrointestinal upset.

If your cat is struggling with prolonged bouts of diarrhea, it’s time to get it to the vet for evaluation. Diarrhea can quickly lead to dehydration which your vet can treat with intravenous or subcutaneous fluid therapy.

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Featured Image Credit: Pixel-Shot, Shutterstock