Food Allergies In Dogs: Causes and Cures

person holding brown and black airedale terrier puppy licking ice cream on cone

Key points

  • Food allergies are one of the most common types of allergies in dogs. Statistics show that around 10% of canine allergies are caused by food.
  • The symptoms of food allergies in dogs include itchiness, diarrhea, vomiting, and lethargy. Some of the less common symptoms are itchy paws, hot spots, eye discharge, alopecia, ear infections, and behavioral issues.
  • Food allergies are not the same as food intolerances. However, their symptoms are similar. A food allergy involves an immune system response to a specific product, and food intolerance means that your dog can’t digest or tolerate a particular product.
  • If your canine has non-seasonal skin and gastrointestinal symptoms that have begun in puppyhood and the reaction doesn’t go away after administering steroids, it’s likely that your dog has food allergies.
  • The only effective treatment for dog food allergy is to eliminate the foods that cause the reaction from the pet’s diet. Your dog should also follow a special hypoallergenic diet.
  • Always consult with your pet’s vet and obtain a treatment plan before trying any remedies.

Pet allergies are probably one of the most triggering and frustrating conditions for any pet owner because of how tricky it is to diagnose and treat them. Food allergies, for instance, are among the top five most common allergies and intolerances in dogs. Many dogs also suffer from two types of allergies simultaneously, such as food and environmental allergies. Unfortunately, the symptoms of these two allergy types are almost indistinguishable, which makes it hard to determine the allergen. In this article, we’ll take a closer look at food allergies in dogs and provide some tips on how pet owners can diagnose and treat their allergic pets.

What Is Food Allergy In Dogs?

An allergy is a natural bodily response to so-called triggers. The allergen (a specific protein or carbohydrate) triggers the immune system, which results in the production of antibodies called immunoglobulin E (IgE) against a portion of the food molecule. Surprisingly, dogs are more likely to develop an allergy to a particular product if they consume it regularly for a prolonged period of time.

Food Allergy Symptoms In Dogs

If your dog is allergic to one or more components present in its food, it may develop the following symptoms:

  • Itchiness
  • Gastrointestinal disturbance such as diarrhea and vomiting
  • Lethargy
  • Weight loss
  • Itchy paws
  • Hot spots
  • Dandruff or oily skin
  • Skin pigmentation
  • Eye discharge
  • Red eyes
  • Alopecia (hair loss)
  • Ear infections
  • Secondary yeast or bacterial infections of the skin or ears

More rare allergy symptoms include nasal discharge, breathing issues, seizures, and secondary urinary tract infections.

Sometimes, food allergies can result in behavioral issues such as hyperactivity and aggression. For example, if your dog feels discomfort because of an allergy, it can start scratching at the furniture or even your legs. You may also notice the pet frequently shaking or scratching its ears, biting its paws, rear end, and tail, and refusing food.

Long-Term Allergy Effectsbrown and white short coated dog wearing yellow and green shirt lying on orange textile

Even if your pet is displaying only mild symptoms of food allergies, you can’t leave this condition untreated because it’ll impact the pet’s quality of life. Untreated allergies can cause the pet to develop secondary skin infections, other allergies, and behavioral issues. Plus, allergy symptoms can worsen over time.

Canine allergies are not lethal, but you wouldn’t want to experience discomfort and itching on a daily basis, so why should your dog?

Most Common Food Allergens For Dogs

Every product can potentially cause an allergic reaction, even food additives and spices. But the most common culprits of food allergies in dogs include gluten (usually from wheat) and proteins in dairy products, chicken, beef, lamb, chicken eggs, or soy.

raw chicken meat on brown wooden chopping board

Keep in mind that if a vegetable contains even a tiny amount of protein, it may not be safe for your dog. For example, while potato starch is safe for dogs, whole potatoes can cause an allergic reaction because they contain proteins.

Pure fats such as fish oil are not likely to cause allergies, but they can be contaminated with proteins during processing.

Gelatin can also trigger an immune response in some dogs, so be careful when giving supplements to your dog since they are usually encased in gelatin capsules.

Even though peanut allergies are very common and dangerous in humans, they are quite rare in dogs. Even if your dog is allergic to peanuts, the symptoms won’t be as serious as with other types of allergies.

How To Know What My Dog Is Allergic To?

Here are some signs that your pet is suffering from food allergies:

  • Your dog experiences both skin and gastrointestinal symptoms
  • The symptoms developed during puppyhood—it’s unusual for small puppies to experience environmental allergies
  • The reaction doesn’t respond to steroids
  • The symptoms aren’t seasonal, and they don’t change with the climate and environment

Allergies to fleas and environmental components are far more common than reactions to food, so you should consider those allergens first. But if you’ve eliminated all other possible causes and your dog is displaying the signs listed above, then there’s a significant chance that the pet may be suffering from a food allergy.

Food Elimination Diet

black pug wearing red and white santa hat

The easiest and most precise way to diagnose food allergies in pets is to use an elimination trial. During this trial, you will need to feed your pet a special hypoallergenic diet for 8 to 12 weeks. This hypoallergenic diet should not contain any products that your dog has been exposed to in the past. It also eliminates all flavored supplements and medications. The idea is to feed your dog food made up of one protein and one carbohydrate source and slowly introduce other ingredients back into its diet. The transition to the new diet should be slow too, and it should usually take about 7 days.

Keep in mind that this trial should be done only under the guidance of a licensed veterinarian who can recommend the right hypoallergenic food and help you find the right treatment plan for your pet.

A vet can also perform blood, hair, or saliva tests to determine the allergen. Blood tests that help to determine the allergy trigger are called serum IgE tests. Your vet will decide whether they can help to diagnose your canine’s condition.

Patch tests are also very common in allergy diagnosis. To carry out the test, the vet will mix the suspected protein with petroleum jelly, tape a bit of the mixture to the pet’s skin, and leave it for about two days. If there’s irritation after the patch is taken off, it means that the test is positive and the pet is allergic to the protein. If there’s no irritation, the test is negative.

Ways To Treat Food Allergies In Dogs

Avoid The Allergen

As soon as you determine what allergen is causing your pet to experience an allergic reaction, you should eliminate it from the dog’s diet.

But unfortunately, if your dog has developed one food allergy, there’s a risk that it’ll develop other food-related intolerances. Luckily, the pet food market offers an innumerable amount of hypoallergenic diet options for pets, as well as numerous protein substitutes. For example, if your dog is allergic to conventional meat-based food, switching to insect-based protein will be a great option for you to consider. Insect-based pet food is a natural alternative that is as high in protein as conventional meat-based kibble, but it also has a higher nutritional value and is more eco-friendly. Thousands of pet owners have tried and loved PetCan’s insect-based dog food, so it’s your turn now to give it a try.

Special Diets

Your vet may also recommend that you switch your dog to a prescription formula, grain-free, or limited-ingredient diet. While a limited ingredient diet contains a restricted number of ingredients, grain-free dog food can contain anything except wheat, corn, or soy. These products are sometimes associated with food allergies, and that’s why grain-free diets are so popular among pet owners.

Many pet owners also decide to feed their dogs home-cooked meals, but unless they are formulated by a veterinarian, many home-cooked meals for dogs lack essential nutrients.


Your vet can recommend antihistamines like Benadryl to ease your dog’s itchiness. You can also use anti-itch shampoos and ointments, but make sure your vet approves any remedy that you’re planning to use. Antibiotics and antifungals can help with secondary infections, but they are useful only in the short term, and the symptoms may reoccur after stopping the treatment. Steroids that are anti-inflammatory medications don’t relieve most of the symptoms.

The Difference Between Food Allergies And Intolerances

Food allergies and food intolerances are accompanied by similar symptoms, which is why many people use these conditions interchangeably. Both of these conditions belong to the category of adverse food reactions, or CAFRs. True allergies are far less common than food intolerances. The difference lies in the fact that, unlike a true allergic reaction, food intolerance doesn’t involve an immune response. If a pet is intolerant to a certain product, it simply means that your dog’s body can’t process it.

Are Dogs Genetically Predisposed To Food Allergies?

It seems logical that if a parent has an allergy, then there’s a chance that the offspring will inherit it. But do genes actually play a role in a pet’s predisposition to food allergies?

While there is some evidence that shows that genes can impact the chance of your pet developing a food allergy, there’s no scientific proof that some dog breeds are more predisposed to food allergies than others. The same is true for sex and age, as these factors don’t influence how likely a pet is to develop food allergies and intolerances.


How long does it take for a dog to react to a food allergy?

Itchiness and skin irritation symptoms such as hives usually appear within 6-24 hours after the pet ingests the allergen.

Can a dog suddenly become allergic to his food?

Yes, it’s common for dogs to become allergic to products they’ve been exposed to for a long time.

How do you treat food allergies in dogs?

The only way to prevent a pet from experiencing an allergic reaction is to avoid the products that cause it. Your dog will likely need to follow a hypoallergenic diet for 8-12 weeks so your vet can determine what product the pet is allergic to.

What is the most common food allergy in dogs?

The most common products that cause allergies in dogs are wheat and proteins contained in meats, dairy products, soy, and chicken eggs.

What natural remedy can I give my dog for allergies?

You can use hypoallergenic shampoos and ointments to ease skin irritation. Aloe vera and oatmeal are also known to help with itchiness and allergy symptoms.