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Food Allergies in Cats

Food allergies are common in cats.

Food allergies are more common in cats that many people previously thought. Flea allergies and inhalant allergies are also extremely prevalent.

Signs of Food Allergies in Cats

When cats are allergic to some component of the food they are eating, they often develop severely itchy skin. Small, translucent bumps can appear on the skin as a result of the body's over-reaction to the substance. Those bumps are quite itchy, and the cat will usually scratch at the skin with a rear paw or lick and bite incessantly at himself.

Often, the small, clear bumps on the skin aren't noticeable to us when they appear because they're under the fur. And by the time we discover there's a problem, the cat's licking or scratching may have disguised them. Red, inflamed skin with hair loss and raised, red bumps are more likely to be noticed after trauma from the cat's tongue or claws has occurred.

In many cases, food allergies in cats cause itchy skin mainly around the face and neck. That isn't always the case, of course, but that common pattern can help a veterinarian narrow in on the suspicion of a food allergy.

Some cats develop gastrointestinal signs along with or instead of itchy skin when they have a food allergy. Those cats might have increased vomiting, persistent diarrhea, bloating, gas, decreased appetite, and weight loss.

Cats of all ages can have food allergies. Additionally, a cat that has eaten the same diet for many years can develop an allergy to some component. Therefore, food allergy can't be ruled out simply because the cat hasn't received any new treat or food.


Diagnosis of Feline Food Allergies

The diagnosis of food allergies in cats isn't always straightforward. Many times, secondary skin infections can complicate the diagnosis in cats showing itchy skin as the primary sign of their condition. And vomiting and diarrhea can have many triggers, so testing must often be done to rule out other causes.

Many times, when a cat is first presented with itchy skin, the veterinarian will perform some skin tests to help narrow down the issue. He or she might perform a skin cytology, culture, or scraping. Flea preventative will almost always be prescribed to ensure the problem isn't flea allergy because cats are so fastidious in their grooming that it can be challenging to find fleas or flea dirt on them.

While there are blood tests that can be sent to the lab to look for signs of food allergy, they aren't considered by most veterinarians to be highly accurate. The gold standard way of diagnosing food allergy in cats is by doing a food trial.

How Does a Feline Food Trial Work?

When your veterinarian recommends a food trial for your cat, he or she will prescribe a specific diet to use. That diet will either be a hypoallergenic diet that contains hydrolyzed proteins, which the body is unable to create an immune over-response to, or a novel diet, which contains a protein source radically different from any in over-the-counter cat foods, like kangaroo or duck. These diets also contain a carbohydrate source which is not used in over-the-counter feline foods, like sweet potato. Alternatively, the doctor may recommend a homemade diet, but those must be cooked carefully using a specific recipe developed by a veterinary nutritionist. Otherwise, serious health problems could occur for the kitty.

The veterinarian will probably instruct you to switch your cat's diet slowly over to the food trial diet. Once your cat is eating 100% trial diet, you will watch the signs carefully. It can take six to eight weeks for all the components of the previous diet to be flushed from your cat's system, so you must continue the trail for at least eight to ten weeks to see if the signs disappear.

It's crucial that, during the food trial, your cat doesn't receive anything other than the special diet to eat. That includes treats, flavored toothpaste, medication flavored for easier administration, and table scraps. Anytime your cat gets something other than the special diet, the clock starts over on the eight to ten-week trial.

Treatment of Food Allergies in Cats

Once the veterinarian determines that your cat has a food allergy through the use of a food trial, you will have two choices:

  • Keep him on the trial food long-term.
  • Challenge him with other protein and carb sources one at a time until you find out which ones specifically cause him a problem. Then choose over-the-counter food that doesn't contain those components.

During the food trial, your cat might need treatment for secondary skin infections or to decrease the itch to a manageable level for your cat while you wait for the trial to progress.

Prognosis for Cats with Food Allergies

Once the problem is diagnosed and a type of food is found that doesn't trigger his issue, the prognosis for a cat with food allergies is excellent. The process of diagnosing the problem can take some time.

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Skin Culture and Sensitivity Testing in Cats

Ear Infections in Cats

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