Dog laying on floor eating loose kibble

How to know if your dog has a food allergy

It’s easy to be confused about dog food allergies. You would be surprised how often we take questions from someone who is concerned that their dog has an allergy when what they’re actually dealing with are symptoms of food intolerance. Intolerances to foods are uncomfortable and can build up to drastic symptoms over time. However, they do not involve an immediate immune reaction and are instead a subdued response to a component in your dog's food that can be harmful to them.

An allergy, on the other hand, is a condition that results from an immediate immune system reaction to a foreign substance such as pollen or certain foods. Dogs can develop allergies to almost any type of food. However, the most common allergens are proteins in chicken, beef, dairy products, gluten, and eggs. Other potential allergens include corn, wheat, rice, barley, oats, and soy.

Is it an allergy, or something else?

Food allergies are less common than food intolerances, but allergies are more severe. Food allergy symptoms could be as sudden and extreme as an anaphylactic shock that triggers an immediate, often life-threatening situation for your dog due to a rapid decrease in blood pressure. Other, more mild allergic reactions often cause things like skin problems. This might include things like hives (red itchy bumps on the skin) and swelling around the face. This is often seen with other symptoms like vomiting and diarrhea. Again, because this is an allergic reaction, these symptoms come on rapidly, even if they're less severe than anaphylactic shock.

The most common symptoms of dog food allergies are gastrointestinal issues, such as gas, vomiting, and diarrhea, skin issues like itchiness, rashes, and infections. Other symptoms may include swelling in the lips, eyelids, or ear flaps.

What is the difference between a dog food allergy, and dog food intolerance?

Dog food intolerance is usually a long-term condition that does not involve an immediate immunological response. It usually occurs after a prolonged period of time, and only after a significant amount of the food has been consumed. Food intolerances aren't typically life-threatening, but they are a nuisance. Why? Because food intolerances cause remarkably similar conditions to a food allergy. 

The most common symptoms of food intolerance are gastrointestinal reactions like gas, inconsistent bowel movements (normal one time, constipated or loose the next), weight loss, lack of appetite, and even vomiting. Food intolerances also lead to the same skin issues suffered by a food allergic dog.  The biggest difference between the two being that one is an immediate histamine reaction upon eating (an allergy), while the other gradually develops over time as irritation and inflammation build up (intolerance).

For example, in the early stages of food intolerance, the symptoms may be just a dull coat and dry or greasy skin. Over time this can be accompanied by excessive shedding, itching, and scratching or chewing to the point of damaging the skin.

How dog food allergy is diagnosed

Your vet can do a series of tests to determine if your dog is having allergic reactions to something they're eating. However, an easier way of accurately determining if your dog is having a negative reaction to their food is to use an elimination diet.

You can try feeding a limited-ingredient diet that contains novel proteins (things like duck, rabbit, lamb, or fish), for eight to twelve weeks without deviating. If your dog's symptoms clear up, they are either sensitive to their old food or have an allergy to one or more of the ingredients.

Treatment for dog food allergies and intolerances

Lasting treatment for both conditions typically involves removing potential allergens or irritants from your dog’s diet long enough for the symptoms to go away. Once your dog is feeling better, you would then have the option to slowly begin reintroducing different foods and ingredients one at a time. This way, you can tell which (if any) ingredients your dog is allergic to. 

For example, if your dog experiences any symptoms after eating a certain food, then you know that food contains an allergen or irritant. From there, you'll need to find a dog food formula that is free of allergens or make your own dog food.

Note: if your dog has experienced an allergic reaction or has shown symptoms of food intolerance, it’s a good idea to fortify their system with healthy supplements. Probiotics, Omega 3s, and brewer's yeast (for the B Vitamins) help your dog’s gut and skin recover from the damage it likely experienced.

Wrapping Up

Dogs can develop allergies to a variety of different things, including food. Symptoms of dog food allergies can include things like anaphylactic shock, gastrointestinal issues, and swelling in the face. All of these symptoms come on rapidly after eating. The best way to diagnose a dog food allergy is through a vet who will likely recommend an elimination diet.

Treatment for dog food allergies typically involves eliminating all potential allergens from your dog’s diet—this includes treats too, not just their primary diet—and only reintroducing ingredients one at a time. If your dog experiences any symptoms after eating a certain food, then you know that food contains an allergen or irritant. From there, you'll need to find a dog food formula that is free of allergens and irritants or make your own dog food. Dogs with food allergies should always be supervised when eating in order to avoid any potential reactions.

Thanks for reading our overview of dog food allergies and intolerances, how to identify them, and how to prevent reactions! If you have any questions, we're always happy to help! Feel free to give us a call, shoot us an email, or stop by your local Kahoots Pet and Feed store.