Cat Food Intolerance Testing

Cat food intolerance occurs when pets react adversely to certain ingredients or foods that they have consumed. Most cats that suffer from food intolerance exhibit symptoms that are similar to a stomach upset in humans. Although the cat develops intolerance to certain ingredients, this condition shouldn't be confused with feline food allergies. Food allergies typically occur when the cat's immune system reacts aggressively to any food that has been fed to the cat for a long period of time. Some examples of known food allergens include corn, fish and certain dairy products. Cats also develop intolerance to the same foods that cause allergies. It's therefore important to conduct a cat food intolerance test to find out the true cause of the condition.

Distinguishing Allergies from Food Intolerance

Most pets that experience food intolerance show signs of diarrhea, vomiting, pain in the abdominal area and disinterest in food. Pets that develop allergic reactions on the other hand, show signs of itching, hives and facial swelling. Since the cause of allergies and food intolerance is fairly similar, it's important to conduct tests to find out what the cat is really suffering from.

Food Intolerance Testing

If the cat shows no signs of skin reaction, the vet will ask you to withhold food until the cat stops vomiting and passing loose stools. The cat will then be placed on a bland diet until he recovers. The vet will perform a food trial on your pet to find out which food triggers intolerance. Although there are several commercially available diets that are fed during food trials, you can choose to feed your cat any source of protein that he hasn't consumed before. Duck meat or rabbit meat is a good option. If you don't want to feed the pet commercial prescription diets, prepare the cat's meal in accordance with the vet's instructions. This diet should be fed for nearly 8 weeks and the cat shouldn't be given any table scraps or treats during this testing phase. After the 8 weeks have passed, the vet will ask you to introduce one of the ingredients that were previously present in your cat's food. If the cat doesn't feel sick, this ingredient isn't the likely cause of intolerance. One by one, you will have to keep reintroducing ingredients to the cat's diet to find out which one triggers food intolerance.

Tips for Pet Owners:

  • Make sure your pet doesn't ingest any food that's fallen on the floor during the trial
  • Avoid giving your cat any treats, rawhides or flavored toys
  • Prevent the cat from roaming outdoors and ingesting anything like contaminated food, water or soil 
  • Take the cat for periodic vet checks


After the cause of food intolerance is identified, make sure you avoid feeding that ingredient to your pet. If you want to feed the cat commercial food, read food labels carefully to determine if they contain the ingredient that causes intolerance. Home cooked diets are recommended but they might lack the recommended daily intake of vitamins and minerals and you might have to supplement the cat's diet.

Although food intolerance isn't a very serious condition, it does take some time and effort to determine the cause.