Written By: Tiffany Ruiz Dasilva, VMD, cVMA | Professional Services Veterinarian, Wild Earth

Itching, scratching, recurrent ear infections, vomiting, and diarrhea — does your dog have some or all of these symptoms? If so, they could be suffering from food allergies.

In this article we will explore the common signs of food allergies, how to find out if your dog has them and what you can do about it.

Dog Food Allergies vs Intolerances

First of all, not every food or ingredient that causes symptoms in your dog is the result of an allergy. Many times, an adverse reaction can be caused by a food intolerance.

What’s the difference? It has to do with whether or not there’s an immune response to the food.

A food intolerance occurs when a dog has difficulty digesting or processing certain food components, resulting in digestive disturbances or non-immune system-related symptoms like diarrhea or vomiting.

But with a food allergy, an immune system response is triggered by proteins in the dog's diet. This response triggers the release of chemicals such as histamines within your dog’s body, resulting in allergic symptoms, including itching.

Dog Food Allergy Symptoms

Now, let’s take a look at the signs of food allergies to watch out for in your furry friend. But first, know that when it comes to symptoms, no two cases of dog food allergies are exactly the same. Your dog may experience any combination of the symptoms listed below.

The most common signs of a dog food allergy are the same as you’d expect from humans with food allergies. However, these symptoms don’t rule out the possibility that your dog is allergic to something besides food.

Excessive Itching

If your dog is scratching year-round, your dog may have food allergies. Dogs with food allergies tend to itch year-round, regardless of the season. The most common spots to see your dog itching with food allergies are paws, ears, underarms, and rear end.

Secondary Hair loss and Skin infections

If a dog scratches, licks or chews their skin excessively, they may cause hair loss in that area. Additionally they may injure their skin, which can allow for bacteria to get into the wound and cause an infection.

With either of these symptoms, there are complications you have to watch out for. Namely, your dog can scratch the affected areas so much that they damage the skin, create patches of hair loss, and even cause infections.

If a dog scratches or chews their skin excessively, they may open up the skin—and then keep scratching some more. The bacteria in their environment, claws, or teeth may get into the open sores and cause an infection. Bacterial skin infections are often treated with antibiotics, so be sure to visit your veterinarian as soon as any severe itching and scratching begin.

Recurrent Ear Infections

Dogs with food allergies may develop allergic otitis, which is inflammation of the ear canal that can be caused by an allergic reaction. This can result in recurrent ear infections characterized by symptoms such as redness, itching, odor, discharge, and discomfort. The dog may frequently shake its head or scratch at the ears in an attempt to alleviate the itchiness. About 65-80% of dogs with food allergies experience recurrent ear infections.

Gastrointestinal Symptoms

Contrary to popular belief, a smaller percentage of canines experience gastrointestinal symptoms as a result of an allergic reaction. These symptoms include:

• Vomiting
• Diarrhea
• Bloody diarrhea
• Constipation
• Abdominal pain or discomfort

If these happen only once in a while, they’re most likely not from food allergies. But if these are chronic conditions, food allergies could be the cause.

Behavioral Symptoms

Behavioral changes secondary to these food allergy symptoms mentioned may also occur. These include:

• Frequently scratching or shaking their ears
• Excessive biting of paws, rump, or tail
• Frequent rubbing against furniture and other objects to itch
• General restlessness

Signs Your Dog Has a Food Allergy and Not an Environmental Allergy

Allergy symptoms can be the same whether the allergy is caused by food, environmental or contact allergens, or fleas. So how can you differentiate between them?

Well, as mentioned food allergies typically occur year-round and dogs are usually itchy on their paws, ears, underarms, and rear end. These allergies generally begin around age 2 and can occur to the same food they have been eating their whole life.

Dogs with environmental allergies, on the other hand, typically only itch during seasons when grasses and pollens are highest, and common locations affected are face, feet, underarms, ears and belly.

Lastly, dogs with flea allergies, another common type of allergy in dogs, are allergic to the saliva of the flea. They typically have itching and hair loss on the rear end, and it is usually seasonal as prevalence of fleas ebbs and flows throughout the year. An important step in ruling out the cause of your dog’s itch is to make sure your pet is on a year-round prescription flea preventative prescribed by your veterinarian. Most flea preventatives found in pet stores require the flea to bite to kill them, so it is important to choose one that prevents the flea from biting in the first place if your dog is allergic to fleas.

Unfortunately there is not always a clear culprit, and allergic dogs may have a combination of two or more of these common allergies- meaning that a dog with a food allergy can also have an environmental allergy!

Common Causes of Dog Food Allergies

Contrary to popular belief, food allergies are not always accompanied by gastrointestinal signs such as vomiting and diarrhea, and the most likely culprit is not grain. Instead, the most frequently reported food allergens involved in cutaneous adverse food reactions are animal based products such as beef, dairy, and chicken. This recent study revealed that animal-based ingredients (beef, dairy, chicken, lamb, egg, pork, fish, and rabbit) were responsible for over 3 times the amount of food allergy cases in dogs than plant-based ingredients.

This is why our high protein, plant-based dog food is a great choice for dogs with food allergies. Take a look for yourself and see the many examples of dogs who no longer suffer from chronic itching, licking, inflammation, and more after switching to Wild Earth.

How To Diagnose Food Allergies?

The best way to be sure about whether or not your dog has food allergies is to take them to the vet. Food allergy diagnosis is typically done with a food elimination trial, where a dog is fed a hypoallergenic or novel protein dog food for 8 to 12 weeks to see whether their symptoms are eliminated. If they are, they likely have a food allergy, and this can be confirmed by reintroducing the offending food to see if an allergic response is triggered (although this step is typically skipped to spare your dog the itching).

During this time, your veterinarian will treat any skin or ear infection, and may also recommend that your dog be on anti-itch medication such as injections or allergy medication to provide quick relief.

It is important that you completely eliminate animal-based products, including those given as treats, supplements and/or in flavored parasite preventatives. For flea/tick/heartworm preventatives, I recommend using these year-round, so be sure to switch over to an unflavored version or one free of animal-based proteins.

Wild Earth: A Great Choice for Dogs with Food Allergies

As I have mentioned, Wild Earth is free from the most common food allergens for dogs, making it a great choice for dogs suffering from food allergies. If you suspect your dog has food allergies, make the switch! And don’t forget, our treats are also free of the most common allergens so you can use them to show your pup just how much you love them - without the itch!