Think Your New Dog Has Food Allergies? Here’s What to Do Next

Adopting a dog requires a lot of preparation, but if your new pup comes with food allergies (or starts showing signs of them after adoption), it can add another layer of complexity. Dogs with food sensitivities require a bit of extra care and attention to support their health.

The good news? With the right knowledge and approach, managing your dog’s diet doesn’t have to be daunting. Once you’ve gone through the initial investigation and made the necessary dietary changes, caring for your dog will feel like caring for any other pet. 

Learning about common allergens, how to tell if your dog is allergic to their food, and how to create a safe, nutritious meal plan are key steps to ensuring your newly adopted dog thrives in their new home.

What are dog food allergies?

Food allergies in dogs occur when their immune system mistakenly identifies certain proteins in food as invaders (rather than food items) and mounts an immune response, which results in a variety of symptoms. 

A food allergy is different than a food intolerance. With an intolerance, a dog may struggle to digest certain ingredients, resulting in symptoms like vomiting, diarrhea, or bloating, but this doesn’t stem from an immune response. 

Signs of food allergies in dogs

Food allergies in dogs can manifest in various ways, often affecting their skin and digestive systems. Here are some common signs to look out for.

• Itchy skin: Itchiness (especially around the ears, paws, and face) is a common symptom. 

• Chronic ear infections: Persistent ear infections, particularly if they don’t respond to treatment, can be another sign.

• Gastrointestinal issues: Vomiting, diarrhea, excessive gas, or even bloating after eating could indicate a food allergy.

• Red, inflamed skin: This may appear as hives, rashes, or hot spots that make your dog uncomfortable.

• Frequent licking or chewing of paws: Dogs with food allergies may chew or lick their paws as a response to itchiness or irritation.

• Behavioral changes: Irritability, restlessness, or lethargy can sometimes accompany the physical symptoms of food allergies.

Common dog food-allergies

First, some good news: “Food allergens in dogs are not as common as believed,” says Dr. Shannon Vawter, veterinarian and medical director at Thrive Pet Healthcare - Wedgewood in Nashville, Tennessee. She says dogs are more likely to be allergic to environmental allergens like fleas, mites, grass, and pollen.

That’s not to say that food allergies don’t occur. Dogs can develop allergies to a variety of ingredients found in commercial dog foods. Below are the most common categories of food allergens.

Protein sources

“When considering food allergens, the most common triggers are proteins, such as chicken, beef, dairy, and eggs,” Dr. Vawter says. “Proteins such as fish, lamb, and pork are less likely to cause allergies, although it is still possible.” 

Grains

Dr. Vawter says reactions to wheat, oats, rice, and corn are rare but not impossible. If your dog is diagnosed with a grain allergy, opting for grain-free food that uses alternative carbohydrate sources like sweet potatoes may help manage their symptoms.

Legumes

Another less common food allergy in dogs is legumes, which include ingredients like peas, lentils, beans, and soy. Legumes are often used as fillers or alternative protein sources in grain-free dog foods.

Additives and preservatives

Synthetic ingredients including artificial colors, flavor enhancers, and chemical preservatives (such as BHA, BHT, or ethoxyquin) can occasionally trigger sensitivities in highly sensitive dogs — though these cases are very rare.

Dog food allergy diagnosis

If you suspect your dog has a food allergy, here’s what to do. 

Visit your vet

Your first step should be to consult with your veterinarian. But don’t expect a quick answer. Pinpointing food allergies in dogs can be challenging, because there aren’t specific tests available for them, Dr. Vawter explains. 

She adds that dogs may react to multiple ingredients — and even environmental allergies like grass or pollen — which can further complicate the process of identifying the root cause. 

Do an elimination diet

“A veterinarian or dermatologist will usually start with an elimination trial,” Dr. Vawter says. This involves feeding your dog food with novel protein and carbohydrate sources (ones they haven’t been exposed to before).

Diagnostic food trials typically last around eight weeks. It takes about four weeks for a dog’s immune system to begin adjusting to the new diet, and full improvement may take eight weeks (or sometimes a bit longer). During this period, your dog must stick strictly to the prescribed diet — no extra treats, unapproved dog food, or table scraps. Any off-diet snacking could interfere with the results and potentially require you to restart the trial.

A veterinarian may also recommend starting with a hypoallergenic dog food. These foods are hydrolyzed, meaning the proteins are broken down into tiny molecules that are too small for the dog’s immune system to detect as allergens. Dr. Vawter explains that if your dog’s symptoms improve while on this special diet, a food allergy is the likely cause. 

Introduce ingredients

Once your dog’s symptoms have cleared up, your vet will guide you through a “challenge” phase, where you’ll reintroduce the suspected allergen. If your dog’s symptoms return, you’ve identified the culprit. If no symptoms appear, try reintroducing another ingredient. Repeat this process until a reaction occurs, which will confirm the specific ingredient that is triggering your dog’s allergies.

Dog food-allergy diagnosis treatment and management

Here’s how you can treat and manage your dog’s food allergies effectively.

Stick to the new diet

If your dog’s symptoms improve on a hypoallergenic diet or your vet identifies a specific allergen via an elimination diet, it’s crucial to stick with dog food that avoids the triggering ingredient(s). Consistency is key to managing food allergies, as even small amounts of the allergen can cause a reaction.

Manage symptoms with medications

While diet changes address the root cause, medications may be prescribed to manage immediate symptoms. Antihistamines or steroids can help reduce itching, inflammation, or other allergic reactions while transitioning to a new diet.

Always check labels

Become a pro at reading labels to make sure any food or treats you give your dog (or that other people give your dog) are free from the suspected allergen. Even trace amounts of certain ingredients can trigger an allergic response in highly sensitive dogs.

Avoid cross-contamination

Cross-contamination happens when allergenic substances accidentally come into contact with your dog’s food, often through shared surfaces, bowls, or handling. For example, if you prepare food containing an allergen and then use the same utensils, trace amounts of the allergen could make their way into your dog’s meal.

This is especially important if you have multiple pets, because food bowls or treats for another pet could contaminate the allergic dog’s space or food. To avoid this, keep allergen-containing foods separate, use designated bowls and utensils, and wash your hands thoroughly after handling any food with allergens.

Regular monitoring

Once your dog’s allergies are under control, it’s important to regularly monitor their health and reactions to food. Food allergies can evolve over time, and periodic vet check-ups can help keep your dog’s condition in check.

Commonly asked questions

Are certain breeds more prone to food allergies?

“Some reports suggest that Cocker Spaniels, Labrador Retrievers, Golden Retrievers, German Shepherds, and Poodles may be at greater risk for food allergies, though they can occur in any breed,” Dr. Vawter says.

What is the best dog food for allergies?

The best dog food for allergies typically includes hypoallergenic or limited-ingredient options. These foods often use novel proteins such as duck, venison, or fish and exclude common allergens like beef, chicken, and dairy. In some cases, a hydrolyzed protein diet is recommended, where proteins are broken down into smaller molecules that are less likely to trigger allergic reactions.

How long does it take for food allergies to show up in dogs?

Most dogs consume the problematic food for up to two years before showing symptoms. In some cases, signs can develop as quickly as two months after first eating the offending ingredient. 

Can a dog outgrow food allergies?

Unfortunately, most dogs do not outgrow food allergies. Once a dog develops an allergy to a specific food, they are likely to remain allergic for life. Managing the allergy through diet and avoiding trigger foods is the best approach to keep your dog healthy.

References 

Assessment of Dog Owners’ Knowledge Relating to the Diagnosis and Treatment of Canine Food Allergies

Critically Appraised Topic on Adverse Food Reactions of Companion Animals (2): Common Food Allergen Sources in Dogs and Cats

What Every Pet Owner Should Know About Food Allergies