What are food allergies or food intolerance?

Food allergies / intolerance are caused by a reaction to a particular ingredient, which is usually a protein. Sometimes referred to as an ‘adverse reaction to food,’ it is defined as an abnormal response to a food or food additive. There are two classes of adverse reactions: those in which the immune system is involved (generally called food allergies); and those that occur without an immune component (generally called food intolerances).

Allergies may last a lifetime so the ingredient must be permanently removed from your cat’s food.

What causes food allergies or food intolerance?

It may take months or years before your cat develops an allergic response to a particular food. However, once she's allergic, she will almost always have a negative reaction to that food. Allergic reactions are most commonly associated with protein sources – usually the meat in your cat’s food.

Food: The most common causes of food allergies and food intolerance in cats are beef, milk products and fish.

Damage: Inflammation, infection, surgery and some medications can damage the digestive system and may lead to food allergies or food intolerance.

Age: Food allergies and food intolerance can occur at any age.

Breed: Some cat breeds appear more likely to develop food allergies or food intolerance, including Siamese cats.

Is my cat sensitive to foods?

If your cat vomits frequently, has diarrhea, irritated skin, a poor coat condition or hair loss, then she may have a food allergy. The most common symptoms of a food allergy or food intolerance are digestive upset or skin irritation. If your cat has food allergies or food intolerance, you may notice some of the following signs:

  • Vomiting or diarrhea
  • Flatulence
  • Frequent scratching or hair loss
  • Red, inflamed skin
  • Chronic ear problems
  • Poor growth in young dogs
  • Coughing, wheezing and sneezing

IMPORTANT: Some symptoms of food allergies or food intolerance are similar to those of other serious conditions so consult your veterinarian if you notice any of these signs.

The importance of nutrition

Food allergies or food intolerance may last a lifetime. The main goal in managing allergies or adverse reactions to food is to find and avoid the food ingredient responsible for causing the skin and/or gastrointestinal signs. If your cat suffers from food allergies, it’s even more important to feed the right cat food.

Dietary elimination trials --- removing the ingredient from the food your cat eats --- are the most practical and accurate methods of diagnosing food allergies in cats. The food your cat eats should be balanced and contain as few ingredients and additives as possible. Be mindful to remove access to all other cat food, table food, treats, snacks and chew toys while you are isolating the allergen.

If your cat has an allergic reaction to a certain meat, you may want to try a food with a new protein source - new to your dog, that is - such as duck or venison. If none of this helps, your cat may be allergic to these proteins and will need a food with specially broken-down proteins. For accurate diagnosis and treatment options, always consult your veterinarian and ask them to recommend the best food for your cat’s food allergies

Food Allergy Questions to Ask Your Veterinarian:

  1. Are there any foods I should avoid giving my cat because of her allergies?
    • Ask how human food may affect your cat’s health.
  2. Would you recommend a Hill’s® Prescription Diet® or Science Diet® cat food for my allergies?
    • Ask about special nutritional concerns for your cat
    • How much / how often you should feed the recommended food to your cat
    • Discuss which treats you can feed your cat with the recommended food
  3. How quickly should I expect to see signs of improvement in my cat’s condition?
  4. Can you provide me with written instructions or a handout on food allergies for my cat?
  5. What is the best way (email/phone) to reach you or your hospital if I have questions?
    • Ask if you need a follow-up appointment.
    • Ask if a reminder email or notice will be sent.
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