Food Allergies in Animals

Food allergies account for over 10 percent of all allergies seen in dogs and cats. It is the third most common cause after flea bite allergies and inhalant allergies, also called atopy. Lamb and rice diets have been shown to prevent or treat food allergies, but in many cases they do exactly the opposite. The process of a pet being sensitized to a particular agent in food and the complicated antibody response that occurs in the intestinal tract in pets with food allergies are not very well understood.

Food allergies affect both dogs and cats. There is no strong link between specific breeds of animals and food allergies. Food allergies tend to affect both males and females. They can show up as early as five months of age to as late as 12 years of age. Most cases occur between 2 and 6 years of age and many animals with food allergies also have concurrent inhalant or contact allergies. There is a distinction that needs to be made between food allergies and food intolerances. Food allergies are true allergies and show the characteristic symptoms of itching and skin problems typically associated with canine and feline allergies. Food allergies can result in diarrhea or vomiting and do not create a typical allergic response. Food intolerances in pets would be similar to people who get diarrhea or an upset stomach from eating certain foods. However, both food intolerances and allergies can be eliminated with a diet free from offending agents.

The diagnosis for food allergies is very straightforward. Due to the fact that many other problems can cause similar symptoms, it is very important that all other problems are properly identified and treated prior to undergoing diagnosis for food allergies. Atopy, flea bite allergies, intestinal parasite hypersensitivities, and sarcoptic mange can all cause similar symptoms as food allergies. Once all other causes have been ruled out or treated, it is then time to perform a food trial. Veterinarians used to recommend that a pet only needs to be placed on a special diet for three weeks, but new studies show that in dogs, only a small portion of those with food allergies responded to treatment.

Once a positive diagnosis is determined, the treatment is very straightforward. The owner of the animal has two choices. They can choose to feed the animal a special commercially prepared diet or a homemade diet. Ingredients in some pet foods may cause an allergic reaction in hypersensitive cats and dogs. Reactions are characterized by itching and gastrointestinal disorders and are usually responsive to a protein or carbohydrate source in the diet. Food allergies are the third most common cause of itching and account for about 10 to 15 percent of all allergic skin diseases in canines.

To treat an animal with allergies, the allergen must be identified and removed from the animal’s diet. If present, secondary skin infections are controlled using antibiotics or antifungal treatments. Concurrent allergies must also be controlled. Anti-itching medications may be used in the initial stages of treatment, but generally these drugs are not effective for curing food allergy symptoms and have to be discontinued to allow the correct assessment of food trials.