Could My Pet Be Allergic to Their Food?

Just like people, cats and dogs can have food allergies, too. And like humans, those allergic responses can range from itchy and irritating to severe and dangerous.

Food allergies in pets can begin at any age. They can start even if your cat or dog has been eating the same food for months or years.

Symptoms in Cats and Dogs

If your pet has a food allergy, you may notice:

Itchy skin: Also known as allergic dermatitis, this is the most common type of allergy in pets. Irritated, itchy skin can happen anywhere on your pet’s body. In cats, it often happens on the head and neck. In dogs, it often happens near the:

  • Ears
  • Paws
  • Rear end
  • Stomach

Skin issues: Hives, also known as urticaria, may pop up 6 to 24 hours after your dog eats the food they are allergic to. If your dog has short hair, these itchy red bumps are easier to see. Otherwise, you may have to feel for them. 

In cats, skin irritation may take longer to see. Small lumps filled with fluid may develop over a few months, but they usually don’t pop up overnight.

With itchy skin and hives, there are two side effects of the irritation:

  1. Your pet likely will scratch, bite, and lick the affected areas, which can lead to broken skin. If the skin is open, there’s a chance your pet could get an infection, which would need treatment. 
  2. All that scratching can lead to hair loss.

Tummy trouble: Allergies may cause gastrointestinal issues, such as gas, vomiting, and diarrhea.

Swollen face: You may see swelling in your dog’s lips, eyelids, or ear flaps.

Chronic ear or paw infections: Repeated infections in your dog’s ear or paws may be a sign of a food sensitivity, not a food allergy.

There’s a difference between a food allergy and food sensitivity. For example, an allergy triggers an immediate immune system response. Food sensitivity doesn't. Your dog may have food sensitivity if they are having a gradual reaction to an ingredient in their food.

Continued

Common Allergens for Dogs and Cats

When it comes to food, the most common culprits are:

  • Chicken
  • Beef
  • Egg
  • Fish (for cats)
  • Dairy products

Less common ones include:

  • Corn
  • Wheat
  • Rice
  • Barley
  • Oats

 

Diagnosis

If your vet thinks your dog or cat might have a food allergy, your pet may get:

Allergy testing: Just like in humans, figuring out a pet’s food allergy can take time. First, your vet may try to rule out other things that could lead to a dog or cat’s symptoms. 

Elimination diet: The best way to figure out a food allergy is with one of these, which should only be done under the care of a vet or nutritionist, who may prescribe special food for your pet during the trial.

You need the help of a professional with this. That's the only way to make sure you both find the cause of the allergy and do it in a nutritionally complete way.

Treatment

Most of the time, you can manage food allergies in cats and dogs by making changes to what they eat, so that they avoid their trigger food.

Your vet may prescribe medication or a skin cream to help ease symptoms while they figure out a long-term plan.

It’s rare, but a life-threatening allergic reaction can happen and your pet may not be able to breathe. If that happens, call an emergency animal hospital right away.

WebMD Veterinary Reference Reviewed by Amy Flowers, DVM on August 22, 2020

Sources

SOURCES:

MSPCA Angell: “The Itchy Pet -- Food Allergies in Dogs and Cats.”

American Kennel Club: “How To Tell If Your Dog Has Food Allergies.”

American Kennel Club: “Types of Allergic Reactions in Dogs.”

American Kennel Club: “Dog Allergies: Symptoms and Treatment.”

Cornell University College of Veterinary Medicine: “Food Allergies.”

Cummings Veterinary Medical Center at Tufts University: “What Every Pet Owner Should Know About Food Allergies.”

© 2020 WebMD, LLC. All rights reserved.

Pagination

Get Fetch in your inbox

Veterinarian-approved information to keep your pet healthy and happy.

By clicking Subscribe, I agree to the WebMD Terms & Conditions & Privacy Policy and understand that I may opt out of WebMD subscriptions at any time.