The best foods for dogs with allergies

An allergy is when a dog’s immune system overreacts to something in their environment or food. Dogs with food allergies primarily show skin-related symptoms, such as chronic ear infections and itchy skin and paws. Stomach upset may occur in addition to skin symptoms in some cases, but this is uncommon.

Many dog owners naturally suspect their pet’s food when symptoms like itching or stomach upset appear, but true food allergies are actually uncommon in dogs, and if your dog does have food allergies, the best food for them is a well-balanced diet that doesn’t contain the problematic ingredient(s). To understand food allergies, it’s good for owners to know:

• What are food allergies in dogs
• The best diet for dogs with food allergies
• How veterinarians diagnose and treat food allergies in dogs

Figuring out the true cause of your dog’s symptoms isn’t as straightforward as it might seem. Food allergies are diagnosed with a strict elimination trial to determine if symptoms are due to a food allergy or something else. This process can take several weeks to months to complete. If allergens are identified, the best dog food option can then be recommended based on the allergen as well as your dog’s lifestyle and other underlying health issues. This might include a special therapeutic diet, a carefully chosen commercial dog food, or a home-cooked diet formulated with a veterinary nutritionist.

An online veterinarian can make the food trial process easier by helping you track and interpret your dog’s symptoms between in-clinic visits, offering guidance on next steps, and keeping your care plan on track during what can be a long and sometimes complicated process.

An allergy occurs when the body’s immune system overreacts to a harmless substance (an allergen), causing widespread inflammation. When a dog has a food allergy, their immune system reacts to specific proteins in their diet.

The most frequently reported allergens include beef, chicken, and dairy. Allergies to other proteins, such as lamb, egg, or fish, are less common but can develop, particularly in dogs that have eaten those ingredients as their main protein source for a long time. Grain allergies in dogs are rare, although wheat allergies are sometimes seen. Because food allergies are caused by ingesting a specific protein, switching between brands or flavors won’t help because sometimes the same ingredient might be present in the new food or there might be cross-contamination during processing.

All allergies in dogs, including food allergies, primarily cause skin symptoms, such as:

• Excessive scratching or biting at the skin
• Licking or chewing the paws
• Hair loss
• Hot spots
• Crusty or scabbed skin
• Red, inflamed skin
• Chronic ear or skin infections
• Thick or dark skin or other skin changes

Less commonly, dog food allergy symptoms can include vomiting, diarrhea, and excessive flatulence, but these clinical signs occur more commonly with other health issues. If caused by a food sensitivity, gastrointestinal issues will usually be accompanied by skin symptoms such as itchiness.

Since food allergies in dogs are uncommon, poor skin health is more likely to be caused by a different type of allergy, a fungal or bacterial infection, or external parasites. Dogs with food allergies often have other allergies as well, such as flea allergy dermatitis or environmental allergies to pollen, dust, or grass.

There is no single “best” food for dogs with food allergies since different dogs are allergic to different proteins. The best diet is one that’s well-balanced and doesn’t contain the offending ingredient. The diagnostic process identifies the allergen, making it possible to choose a safe, well-balanced diet that avoids the ingredient while still meeting all nutritional requirements. These diets are generally available as both canned and dry and can take several forms:

• Regular commercial diets that avoid the allergen: Some pets improve simply by switching to a commercial food that doesn’t contain the specific ingredient triggering the allergy (for example, changing from a chicken-based to a fish-based diet).
• Limited-ingredient dog foods: These contain only one protein and one carbohydrate source that the dog hasn’t been exposed to before (such as duck and potato, or venison and pea) to reduce the number of potential allergens.
• Hydrolyzed-protein diets: In these therapeutic diets, proteins are broken down into very small fragments so the immune system no longer recognizes them as allergens. Hydrolyzed diets are considered the most reliable option for diagnosing and managing food allergies, especially when the trigger is unknown.

In some cases, an owner may wish to try a home-prepared diet, and the best way to develop one that is complete and balanced is to work with a board-certified veterinary nutritionist (DACVN). Improperly formulated homemade diets can lead to dangerous nutritional deficiencies or worsen the pet’s health over time.

What to know about hypoallergenic dog foods

Use of the term hypoallergenic on pet food labels isn’t strictly regulated, so you can’t count on it to mean the food is appropriate for diagnosing or managing a true food allergy. Many over-the-counter diets marketed as hypoallergenic still contain common allergens, or they may be produced on shared equipment that allows for cross-contamination with other proteins. Veterinary prescription hypoallergenic diets, on the other hand, are manufactured under controlled conditions and use precisely defined ingredients that are less likely to trigger an allergic response. For dogs with suspected food allergies, it’s best to get guidance from a vet when doing diagnostic food trials or for long-term feeding plans rather than relying on marketing claims.

“When a dog develops itchy skin or a rash, many pet owners think, ‘It can’t be allergies because nothing has changed,’” explains Dr. Jo Myers, a veterinarian on the Vetster platform. “In reality, allergies don’t develop from something new. They happen after repeated exposure to a particular allergen over time. With food allergies, the immune system becomes sensitized and starts overreacting to a food protein the dog has eaten for months or even years.”

Canine food allergies are diagnosed by conducting a dietary elimination trial. The overall goal of the dietary trial is to strictly control what your dog eats, ensuring they consume only a very limited list of ingredients that they haven’t had before and which are unrecognizable to your dog’s immune system and are not common triggers for allergies. It’s then important to watch your dog for signs of improvement. Because treats, flavored medications, and table scraps can also contain ingredients you’re trying to avoid, they must also be strictly controlled.

When a food allergy is the cause of your dog’s symptoms, improvement takes time. It usually takes six to 12 weeks for old allergenic proteins to leave the body and for the skin to heal. Some dogs start to feel better after a few weeks, but most don’t show clear results until after two months of strict feeding on the limited diet.

If your dog seems to improve right away, it’s often because of other factors, such as starting parasite control, treating infections, giving itch-relieving medications at the same time, or something coincidental like a change in the environmental pollen count, rather than the diet change itself.

Once your dog improves, vets confirm a true food allergy by recommending a challenge test. This means reintroducing the old diet to see if symptoms return. If they do, it confirms the food allergy diagnosis and guides which ingredients to avoid in the long term. When it’s determined that your dog’s symptoms are caused by a food ingredient, other ingredients can be slowly reintroduced one at a time, with additional allergens being identified if symptoms return.

Is a food trial the only way to diagnose canine food allergies?

Food trials take a long time and require strict control over what your dog eats; plus, interpreting them isn’t always straightforward. While other tests diagnosing food allergies in dogs do exist, they’re not recommended by veterinary experts. Available allergy testing options include:

• Serum allergy panels (blood testing)
• Intradermal skin testing
• Hair and saliva testing

Blood tests measure antibodies (IgE or IgG) thought to be directed at food proteins. Skin testing is reliable for testing environmental allergens and can sometimes be adapted for food allergen testing. Hair and saliva tests are often marketed to dog owners, but they’re not validated in veterinary medicine and are considered unreliable.

Blood, skin, hair, and saliva testing are not recommended for diagnosing food allergies due to poor accuracy and reliability. Multiple studies show that blood and saliva tests for food allergies in dogs have low sensitivity and specificity. They produce both false positives (showing reactions where none exist) and false negatives (missing true allergies). These tests are also not evidence-based. Peer-reviewed research and consensus statements indicate that these tests cannot reliably diagnose food allergies in dogs.

The gold standard for food allergy testing in dogs is an elimination diet trial with dietary challenge (the process of removing and later reintroducing suspected food allergens). It is the only testing method that’s scientifically validated.

If you believe your dog has food allergies, it’s best to talk to a veterinarian rather than just switching their food. Itchiness, hair loss, and other symptoms associated with food allergies are more likely to be caused by other health issues, both allergic and nonallergic. Confirming whether a dog’s symptoms are due to food or another cause requires a structured process, and working with a vet is the best way to get clear answers.

Dog owners can use virtual care throughout every stage of food allergy management or other skin and digestive concerns. Virtual veterinarians can assess your dog, review symptoms, and provide professional guidance on what to do next, helping you decide whether in-person testing or treatment is needed.

During an elimination diet trial, virtual appointments make it easy to share updates and get timely feedback without leaving home, which helps ensure the trial stays on track. If a food allergy has already been confirmed, a virtual vet can also recommend nutritionally balanced diet options that avoid the offending ingredient and support your dog’s overall health. Virtual care is a convenient and reliable way to get ongoing professional support whenever you have questions or concerns about your dog’s well-being.

What foods are best for dogs with allergies?

The best diet for a dog with a suspected or confirmed food allergy is one that is nutritionally balanced and avoids the ingredient or protein source that triggers their symptoms. Because food allergies develop after repeated exposure to an ingredient, a dog cannot be allergic to a food containing ingredients it has never eaten. This means that a diet meant to help diagnose or manage food allergies usually does not include the same protein sources found in the dog’s current diet.

When a food allergy is suspected, veterinarians often recommend an elimination diet or a hydrolyzed-protein diet to help identify safe options while maintaining balanced nutrition. These diets are carefully formulated to avoid previous exposures and to reduce the chance of triggering a reaction. A veterinarian can help determine which diet is most appropriate based on your dog’s history and needs.

Which foods are best for dogs with itchy skin?

Itchy skin in dogs can have many different causes, including environmental allergies, flea bites or other external parasites, skin infections, and occasionally food allergies. Because food allergies are relatively uncommon compared to other causes, changing your dog’s diet alone rarely solves the problem. However, nutrition still plays an important role in supporting skin health. Diets that provide complete and balanced nutrition with adequate levels of essential fatty acids (such as omega-3 and omega-6), high-quality protein, vitamins, and minerals may help maintain a healthy skin barrier and reduce inflammation. For dogs with diagnosed food allergies, a veterinary-formulated limited-ingredient or hydrolyzed-protein diet is often recommended. If your dog has itchy skin, it’s best to work with a veterinarian to identify the underlying cause and choose a diet that supports overall skin and coat health as part of a broader treatment plan.

What is the number one food allergy in dogs?

The most common ingredients dogs are allergic to include beef, chicken, fish, lamb, eggs, and dairy products. Grain allergies, such as wheat, are less common. Even small amounts of an offending ingredient can trigger allergy symptoms in sensitive dogs, so it’s important to consider everything your dog eats, including treats, table scraps, and flavored medications, when managing a food allergy.

Disclaimer: This article, its content, and its related references do not constitute veterinary advice and should not be considered a substitute for veterinary care. If your pet is showing any symptoms that could indicate a medical emergency, please seek immediate emergency care.