Food allergies are sometimes called food intolerances or adverse food reactions in veterinary medicine. These reactions can occur at any time in a dog’s life and are often triggered by certain ingredients or food additives.
Food allergies can cause mild discomfort in some individuals, but in others, they can be severe and completely debilitating. Unfortunately, dogs can’t communicate when they are having an adverse reaction, so it is important for pet parents to be able to identify the signs.
This guide will help you recognize if your dog has a food intolerance and provide you with information on how to address it. If you need to switch to a new diet quickly, we recommend checking out our review of the best hypoallergenic dog foods.
What causes a dog food allergy?
Food allergies in dogs can have multiple causes. Some breeds, like Cocker Spaniels, German Shepherds, and Irish Setters, are more likely to develop allergies than others due to their genetic makeup. Dogs from a long line of breeders may also be more prone to food allergies. If you’re considering getting a dog, it’s important to research breeders and ask about any known allergies.
Environmental factors like illness, surgery, and antibiotics can also contribute to food intolerance. Antibiotics, for example, can disrupt the gut’s immune system and microbiota, which can make it harder for a dog to process certain foods or nutrients. However, it usually takes multiple exposures to a particular allergen before a dog will have an adverse food reaction.
If you adopt a mixed-breed dog from a shelter or foster family, they may be able to tell you about any known allergies. Plus, mixed-breed dogs are often less likely to develop allergies since they have a more diverse genetic background
What are the symptoms of a food allergy in dogs?
It is important to treat your dog’s food allergy at the first sign of trouble. If left unaddressed, adverse food reactions can wreak havoc on your dog’s digestive system. Many dog food allergies also compromise the immune system, making it more difficult for your pup to fight off bacterial and viral infections.
Even if your dog has not previously presented symptoms of a food-related allergy, it doesn’t mean they’re totally out of the water. In fact, many food intolerances develop over the course of several years. Meaning, pet food that your dog once enjoyed has the potential to be problematic over time. Don’t have the very common thought amongst dog owners that “this kibble was fine yesterday, it must be fine today.“
Stay vigilant and keep an eye out for any of the following symptoms of a dog food allergy:
- Skin lesions or inflammation
- Itchy ears or ear infections
- Vomiting and diarrhea
- Excessive gas
- Weight loss
- Constant itching
- Fur loss
It’s important to note that while most people think a vomiting dog with diarrhea or one with gastrointestinal upset is the biggest allergy indicator, a dog’s skin and ears are far more telling of a potential onset of allergy. The skin is the largest eliminative organ in a dog’s body. When there’s a problem, allergens use a dog’s skin as their primary escape route. If your dog is losing patches of hair, itching frequently or has observable lesions on their face, paws, and ears you could be looking at food intolerance.
Are there dog food allergy tests?
It’s difficult, if not impossible, to test your pet for a specific food allergy. Most vets will tell you that blood tests are wholly ineffective.
However, you can have your vet perform other exams and tests to rule out specific, non-food-related issues. For instance, if the lesions or ears are exuding discharge, take a sample in to be tested. You can also do some skin tests to assess your dog’s susceptibility to environmental allergies. Don’t expect a black-and-white list of what your dog is allergic to.
What is the dog elimination diet?
To diagnose and treat a food allergy in dogs, you need to do a food trial. The most popular way is an elimination diet. If your dog’s symptoms don’t go away during this trial, you should speak with your vet to see if they still think it’s a food-related allergy. You can change the protein and carbohydrate source and start the food trial again until you find the right combination. It’s important to keep a journal of what you have tried so you can avoid certain foods.
To see if the allergy is food-related, you should change your dog’s food to a basic protein and carbohydrate mixture that they haven’t eaten before. Read the label to identify the protein sources you need to avoid. You may need to switch to something exotic like rabbit or venison. You can look online for elimination diet recipes, or you can make your own mixture at home where you can control all the ingredients. Doing it yourself is better because you know what’s in the bowl, and it only needs to be done for a short amount of time. Once you know what triggers your dog’s allergic reaction, you can switch back to a new kibble free of these allergens.
Feed your dog the new formula for 3 to 12 weeks. During this time, the dog’s digestive system will reset. However, this also means no treats, table scraps, rawhides, or bones. Even medications should be avoided unless necessary. Only feed your dog the ‘limited antigen’ food and fresh water.
Monitor your dog’s symptoms and note whether they are reduced or eliminated entirely on the new diet. If so, reintroduce your dog to its authentic food and watch for any issues to return. They should appear within a few days if it’s a true food allergy. Once they do, you have confirmation of food intolerance. Some vets call this ‘provocative testing’.
Once you know your dog has a food allergy, switch back to the new formula with simple proteins and carbohydrates. Reintroduce some of the ingredients found in your dog’s old food one by one with 5 days in between. Monitor your dog’s symptoms, and if you see food allergy symptoms again, the last ingredient you reintroduced is the guilty allergen.
You can repeat the elimination diet as many times as you like until you have two to three options your dog can process without symptoms. You may be able to prevent your dog from developing any more allergies by rotating these novel protein and carbohydrate meals every eight to 12 weeks
Check if the allergy is food-related
Start by changing your dog’s food to a basic protein plus carbohydrate mixture they have not previously eaten. Read the label to identify the protein sources you need to stay away from. You may have to switch to something exotic like a rabbit or venison. The same goes for carbs.
You can search the internet for specialized elimination diet recipes that are designed to limit allergic responses, or you can make a special mixture at home where you can closely monitor all the ingredients in the mix. Doing it yourself is more recommended since you know exactly what goes into the bowl, and it has to be done only over a limited amount of time. Once you know what is triggering your dog’s allergic reaction, you can go back to a new kibble free of these food allergens.
Feed your pup the new formula for 3 to 12 weeks. In this time the dog’s digestive system will reset. Be careful, though! This also means no treats, table scraps, rawhides or bones. Even medications should be avoided unless they’re medically necessary. Only feed the dog with your preferred ‘limited antigen’ food of choice and fresh water!
Next, monitor your dog’s symptoms. Note whether they become reduced or eliminated entirely on the new diet. If so, reintroduce your dog to their original food and watch to see if issues return. They should present within a few days if it is a true food allergy. Once they do, you’ll have confirmation of food intolerance. Some vets refer to this process as ‘provocative testing’.
Find the guilty ingredient(s)
Once you know the dog has a food allergy, you want to switch back to the new formula of simple proteins with carbohydrates. Reintroduce some of the ingredients found in your dog’s old food one by one with 5 days in between. Monitor the dog’s symptoms and if you see food allergy symptoms again, the last ingredient you reintroduced is the guilty allergen.
Most dog owners and dog breeders skip this step because it takes a lot of time to figure out, but if you want to from then onwards choose the right dog food, you want to know what ingredients to completely avoid.
You can repeat the elimination diet as many times as you like until you have two to three regimes your dog is able to process symptom-free. You may be able to prevent your dog from developing any further allergies to these novel protein and carbohydrate meals by rotating them out every eight to 12 weeks.
Common food allergens for dogs
In general, the protein sources in many dog foods are some of the most well-known offenders. Beef products can be especially triggering for dog food allergy sufferers. While this may seem counterintuitive since dogs are primarily carnivores, if the quality of meat isn’t up to par it’s likely to cause upset.
Many pet owners also mistakenly assume that their dogs have iron stomachs and can put down almost anything. In truth, most dogs are lactose intolerant and the dairy products found in many common dog food brands can seriously disrupt their systems. Be careful if you are in need of a puppy milk replacer for nursing newborn pups.
In addition to beef and milk products, some other notable food allergens include:
- Chicken eggs
Just like humans, dogs can also have a severe gluten intolerance. Wheaten Terriers and Irish Setters are notorious for developing celiac in their lifetimes. This results in internal intestinal inflammation that can prevent the digestive system from properly absorbing nutrients. Outwardly this might result in poor coat conditions, rapid weight loss or persistent diarrhea. To remedy this, dogs must be strictly fed grain-free dog food. Feed and treats must be entirely devoid of wheat-derived products like rye, oats, barley.
Should you conclude your dog is allergic to common proteins like beef or chicken, make sure their food is supplemented with alternative protein sources like duck, salmon or whitefish and lamb. If you are able to prepare homemade dog meals, feel free to include offals and boney chunks of meat (chicken necks are loved by most dogs!)
Lastly, allergies in dogs can be traced back to food, environment, or both.
Treating your dog’s food allergy
To prevent allergic flare-ups in your dog, it is crucial to keep them away from any known allergens. Once you have identified what your dog is allergic to, you can start making daily dietary changes to avoid these allergens.
Feeding your dog a well-balanced diet is the best way to keep them healthy. It’s essential to choose a dog food with fewer ingredients and additives to minimize the risk of allergies. Also, make sure your dog can’t access another pet’s food, and avoid giving table scraps. Always check treats and chew toys for potential allergens before letting your dog have them.
Probiotics can help supplement your puppy’s digestive system with good bacteria, which can help prevent allergies later in life. For adult dogs, prebiotics can help feed these good bacteria and keep their systems regular.
Remember that dogs can develop additional food allergies over time so never assume that a new dietary regimen will last over the long term. Stay aware and in tune with your dog’s progress to avoid another slip.
Read all labels carefully before purchasing products and make sure any food you prepare for them at home is replete with the right amount of vitamins and minerals. Typically these recipes are best developed with the help of a vet or animal nutritionist instead of relying on the internet alone. Labels are often misleading, so be wary of marketing claims.
Taking a vested interest in your dog’s food allergy is just part of being a proactive dog owner. In doing so you are bound to spare you, fur baby, any unnecessary pain and can quickly get them on the road to recovery.