What is a food allergy?
Food allergies some times referred to as food hypersensitivity are an immunologic reaction to allergens and requires previous exposure to the allergen to bring about symptoms. Food “intolerance” does not involve the immune system and can occur with the first exposure to a certain foods. Both reactions produce similar symptoms and may be difficult to tell apart without veterinary guidance.
Does this mean my dog is in immediate danger?
Unlike humans with a food allergy animals do not experience the same amount of facial and throat swelling that can be so dangerous. Animals experience food allergies differently!
What are the signs?
The most common sign is non-seasonal itching that may involve the whole body or be focused on the ears, arm pits, groin and feet. Chronic or recurrent ear and skin infections are also typical. Some dogs may even develop vomiting, diarrhea, or excessive flatulence. Symptoms often begin when dogs are young (before one year of age), but may flare up at any time.
Proteins are the cause!
Dogs with food allergies are typically allergic to proteins, which come from animal or plant-based ingredients of the diet. The proteins are broken down into molecules that the immune system misidentifies as a potential threat. Beef, dairy, and chicken are the most common culprits of food allergies in dogs. The development of food allergies, however, takes time. So the dog may have been eating the protein allergen for quite a long time before symptoms develop.
What to feed?
A food trial using a hydrolyzed diet is the only reliable way to diagnose food allergies in dogs. In some cases, we choose a “novel” protein diet. Novel essentially means new, a protein that the body has never seen therefore can not be allergic to. It is possible for animals to develop allergies to novel proteins overtime, so keeping a puppy’s protein sources restricted to 1-2 proteins is ideal.
Hydrolyzed diets are made when animal proteins are broken down into very small molecules that the immune system should not be able to recognize them, reducing the possibility of an adverse food reaction. Examples include Hills prescription diet Z/D Ultra and Purina HA.
No matter what type of hypoallergenic dog food you choose, it should be fed for a minimum of 8 weeks to adequately assess the dog’s response. Most dogs experience at least a partial improvement in their food allergy symptoms within the first 4-6 weeks but, some may require a longer period of time to fully respond. It is important to feed only the hypoallergenic dog food, avoiding all other foods, treats and even flavored medications such as chewable heartworm preventives, medications, pill pockets, etc.