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Food Allergies in Dogs: Symptoms & Treatments

Labrador watching his food

Food allergies are one of the most common chronic diseases in dogs. Some breeds are more prone to food allergies than others, but any dog can be affected. When a dog has food allergies, their immune system reacts to the proteins in their food like a foreign invader, producing antibodies and an immune response to a normally tolerated food.

Dog food allergies work a bit differently than food allergies in people, which can cause some confusion. For instance, dogs usually only develop food allergies after being exposed to a particular brand or formula of food for some time. They aren’t born with food allergies like people. Even if your dog has eaten the same food for years, they can develop an allergy to it – and are more likely to due to the long exposure.

In this article, we’ll take a look a everything you need to know about food allergies. Luckily, these problems are pretty easy to treat without medication.

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Symptoms of Food Allergies in Dogs

dog scratching
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The most common symptom of food allergies in dogs is skin problems. Itchiness is common. However, the itchiness can develop into something worse as the dog scratches and scratches. Eventually, sores and scrapes will develop. If the dog continues to scratch, they will never heal, allowing secondary infections to set in. While food allergies typically aren’t common, they can cause serious discomfort and other issues for this reason.

Dogs may also experience digestive problems, which is usually diarrhea. Vomiting can occur as well. However, this is rare.

Other subtle changes can occur too. For instance, a dog may become more hyperactive or appear fatigued. Some dogs lose weight – perhaps because they are eating less due to discomfort.

What Ingredients are More Likely to Cause Allergies?

Proteins are by far the most common cause of food allergies. Out of all the proteins, dogs are most likely to be allergic to the most common ingredients found in dog food, such as chicken, beef, and gluten. This is likely because dogs simply consume more of these things – not because something about them makes them more likely to cause allergies. The more a dog eats something, the more likely they are to develop an allergy to that thing. Therefore, it would make sense that the most common allergens are also the most common ingredients in pet food.

You shouldn’t necessarily avoid these ingredients if your dog isn’t allergic to them. Again, there isn’t something about them that makes dogs more likely to be allergic to them – they simply get consumed the most.

How Are Food Allergies Diagnosed?

Dog check up

It is very difficult to diagnose food allergies. There isn’t a test the vet can run to determine what your dog is allergic to. Instead, an elimination trial must be used. These trials are pretty straightforward and simple. A true elimination diet involves choosing a new food that doesn’t contain anything your dog was previously eating. However, this can be extremely difficult. There are only so many options on the market, and many companies use similar ingredients.

For this reason, some vets may recommend simply switching the proteins your dog is eating. If your dog currently has a food that includes mostly chicken, switch them to one that contains beef. The dog is most likely to be allergic to whatever is the main protein in the food they are currently eating. This isn’t always the case, though. Dogs can be allergic to anything in their food, technically. Eliminations diets can take quite awhile to figure out.

Luckily, once you know what your dog is allergic to, it isn’t terribly difficult to avoid this ingredient.

Sometimes, specific blood tests may be available to help your dog. However, this is usually only used when the elimination diet has failed.

How Are Food Allergies Treated?

The only way to treat food allergies is to avoid whatever your pet is allergic to. Choose a new diet that doesn’t contain whatever your pet is reacting to. This should stop the reaction. There are many commercial diets available that are limited-ingredient, which are sometimes better for dogs with many allergies. If your dog is just allergic to one thing, it shouldn’t be too difficult to avoid that single ingredient.

Dogs that develop an allergy once are more likely to become allergic to something else. For this reason, you should vary your pet’s diet as best your can. If your dog is allergic to chicken, you may vary them between lamb, beef, and fish diets, for instance. This variation will prevent future allergies and is recommended for all dogs.

Can Food Allergies Be Cured?

Dog eating happy
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No. The dog will be allergic to their allergens for the rest of their life. Luckily, most pets only require a hypoallergenic diet. For most dogs, avoidance is quite easy. Of course, for dogs that are allergic to many things, it can be more difficult to avoid their allergens completely.

Dogs with severe reactions may need medication. However, this doesn’t cure the allergic reaction – it only makes the reaction less severe. Because food allergies tend to be progressive, your dog’s reaction typically gets worse if you continue to feed them their allergens.

Related Read: Dog Allergies: Causes, Symptoms & Treatment


Can a Dog Suddenly Become Allergic to His Food?

Yes. In fact, that’s how most food allergies in dogs develop. A dog eats the same food for years. Eventually, the overexposure sets of the immune system and allows enough time for antibodies to build up. The dog will likely exhibit minor symptoms at first, but these may not be noticeable. Often, pet owners don’t realize that their dog is experiencing food allergies until they notice severe itching, sores, and sometimes even infections.

If you notice skin irritation that isn’t obviously caused by something else, it could likely be your dog’s food. Because dog food allergies don’t act like human food allergies, it doesn’t matter that your dog has bene eating the same food for years. In fact, that could be the reason your dog developed the allergic reaction in the first place.

See also: Allergy Bumps on Dogs (Vet Answer): Hives and Urticaria Explained

Featured Image Credit: Olena Yakobchuk, Shutterstock

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