Dog Food Allergies Symptoms, Causes & Treatments

Ever noticed your dog getting scratchy or shedding incessantly? Does your dog have an irregular eating pattern, looks pale and non-energetic? You may not realize but surprisingly, the causative agent behind all of this is ‘Dog Food’.

Has your dog been feeling sick?

One of the most prevalent concerns amongst dog owners, food allergies, can lead to long-term and fatal consequences if not treated within time.

With our team of experts, veterinarians and dog lovers, we have curated an all-inclusive, comprehensive guide for you to know all about Dog Food Allergies and how to treat or prevent them at the best.

What are Dog Food Allergies?

A dog food allergy is defined as an all immune-mediated reaction following food intake. Dog food allergies are multi-symptomatic. These allergies are because of a food protein that triggers an adverse immune response in dogs.

Your dog's feeling itchy? Could be a food allergy

Proteins are present in most dog meals. They are also present in raw meat as well as grains and vegetables. There is no specific protein that causes the allergy, but the way your dog reacts to the protein can develop unwanted adverse reactions.

Dogs can show varied symptoms while suffering from food allergies, ranging from gastro-intestinal trouble to chronic infections. The best way to solve these problems is through medications and a change in their usual diet.

Food Allergies vs. Food Intolerance

Food allergies are often confused with food intolerance but do not mean the same. While food allergies are a dog’s immune generated response, food intolerance is not associated with the immune system but is the result of a poor digestive tract. Food allergy and food intolerance, are categorized as Cutaneous adverse food reactions (CAFRs). CAFR’s deal with systemic immune responses i.e. hypersensitivity as well as food intolerances.

When suffering from intolerance, your dog’s body may not have a specific enzyme required to digest a given protein. The signs and symptoms of food allergy and intolerance may look similar.

Lactose Intolerance is very common in dogs

One such example, which is very prevalent in dogs as well as humans, is lactose intolerance. The body may not have adequate amounts of the lactase enzyme to digest the lactose content present in milk.

Various studies conducted on pets are analyzed and published in the BMC Veterinary Research. The analysis speaks of the prevalence of CAFR’s amongst dogs and cats, being as high as 62% with the most prevalent symptom being skin diseases and allergies in dogs.

Common Dog Food Allergens

When it comes to allergy from dog food, it is not the ingredient but ‘the protein part’ of it that causes the allergy. Having said that, the most commonly consumed ingredients by dogs would be meat, dairy products, and eggs, etc., all of which contain protein and may cause adverse food reactions.

The most familiar of all food allergens that contain different types of protein would be beef, dairy products, chicken, wheat, etc. Here is a list of the most frequent ingredients found in dog food and the percent of dogs having unwanted reactions due to the same.

Dog Food Allergen
Percentage of Dogs Affected
Dairy Products

It is also to be kept in mind that the list of allergens keeps updating and changing as newer food formulas develop. Not every dog food is the same and their methods of processing are not the same either.

The more common a food is, the higher the chances that your dog may develop allergies.

And for your pet to develop allergies, your dog has to be exposed to the food. Therefore, meat and poultry products that contain the highest amount of protein top the charts for causing allergies.

There is not just proteins that serve as a source of nutrients in dog food but also carbohydrates and fats. These do not have potential chances of causing an adverse food response unless they form a part of a source that may also contain protein, for e.g. fruits and vegetables.

Grains are rich in protein but also contain starch. Carbohydrates in pure form i.e. starch, is safer and free of allergy-causing proteins.

Speaking of fats, they also provide adequate amounts of energy and serve as energy reserves to your pet. But then again, fats have to be in their purest form, free of protein. These can be majorly sourced from fish oil, etc.

Dog food treats are also a potential source of allergy, as they contain a lot of adulterants. You may want to switch to peanut butter as a tasty treat. Dogs are rarely found to be sensitive to peanut butter.

If you are using a combination of dog foods, it may get difficult for you to identify which dog food is causing an adverse response. This is because each dog food is different, and may have different ingredients and different types and amounts of protein.

Dog food and dog treats containing artificial flavors, colors and additives are potential allergens, although they may also generate food intolerance or trigger an adverse response. Food labels don’t always tell the true story. If the food is not fresh, it may develop an unwanted reaction and usually contain a protein that may get allergic.

 Is Your Dog Prone to Allergies?

It is likely that if a parent dog has a particular food allergy, their offsprings may inherit it too. Although, the chances of this happening are very uncertain, but GENES may play a role.

Scientifically speaking, there is no specific breed that is prone to developing allergies. Also, dogs are adaptable to multiple varieties of food, so a change of food from their usual routine should not cause any major difference. The age or sex of the dog does also not hold any relevance in causing allergies. It can happen to any dog, irrespective of age, breed, sex, type, etc.

As per observations, certain dog breeds prone to food allergies are as follows:

  • Boxer
  • Cocker
  • Spaniel
  • German Shepherd
  • Daschund
  • Dalmatian
  • Bulldogs
  • Yorkshire Terrier
  • Pugs

These breeds are more prevalently reared as pets, although unnecessary, they are always prone to allergies.

Signs and Symptoms

There are a range of signs and symptoms observed in dog food allergies, ranging right from the skin, to the ear, legs or in worst cases, chronic diarrhea and digestive disorders. We have listed a few signs to help you identify if your dog is a victim of allergies.

Most Common Symptoms

Some of the most prevalently found symptoms in case of mild or severe dog food allergies are:

    • Itchy Skin or Allergic Dermatitis/Skin Allergies
    • Hives or Urticaria
    • Sneezing
    • Pigmented skin
    • Hairloss
    • Ear Infections
    • Yeast or Bacterial Infections

Gastrointestinal Symptoms

Gastrointestinal symptoms due to food allergies are seen only when the condition is severe. Most food allergies are characterized by skin conditions or infectious conditions. Chronic symptoms in the case of gastrointestinal conditions are:

    • Diarrhea with blood in stool
    • Gas
    • Vomiting
    • Abdominal Pain

Behavioral Symptoms

These symptoms may usually occur as a result of the above-listed symptoms. These could be:

    • Scratching own self using furniture or taking owner’s help
    • Feeling restless
    • Biting paws or end of the tail
    • Low on energy and activity levels
    • Loss of appetite

Other Symptoms

These are secondary symptoms and are not very prevalent. Although, these can be seen in certain dog breeds. The symptoms range from:

    • Nasal Discharge
    • Breathing problems
    • Urinary Tract Infections
    • Excessive Weight Loss

Commonly affected body parts include the ear, paws, inner thighs, and belly region or the eyes.

Adverse Food Reaction

Adverse food reaction is more likely a result of intolerance and not food allergies, although the symptoms are similar. This may often be due to the dog’s system not accepting a protein and it does not involve the immune system. On the other hand, food allergy would directly generate a response through the immune system.

Causes of Dog Food Allergy

When it comes to speaking of the causative factors for dog food allergies, it is important to understand two aspects, how the system works normally and during failure. Let us try to understand both.

  • When It’s All Good

Majority of your dog’s immune system works from the gastrointestinal tract. The parts of the gastrointestinal system, majorly the mouth, stomach and intestine, are responsible for filtering potential food allergens each day.

On ingesting food through the mouth, it first reaches the stomach. This food is broken down into smaller particles by stomach acids and enzymes. These small pieces then reach the small intestine where whole proteins are broken into amino acids. These amino acids are absorbed by cells called enterocytes.

Enterocytes act like guards and carefully filter the essential components and non-essential components for the system. When these intestinal cells end up absorbing the whole protein instead of having them broken down into smaller amino acids, your dog shows symptoms of allergy.Enterocytes of Dog's Immune System The ability of the intestine to prevent the absorption of whole proteins depends upon the mucosal barrier. The mucosal barrier forms the lining of the intestine and comprises structural and immune system components. While structural components prevent the absorption of huge protein structures, the immune system components help in filtering harmful substances from the gastrointestinal tract.

One very essential part of the immune system components are the IgA cells (Immunoglobulin A cells). These cells act like guard cells on the walls of the intestine and prevent whole proteins from coming in contact with enterocyte cells. The potential allergens and huge proteins that are not required get stuck to the IgA and are sent back for digestion. The smaller proteins and amino acids pass the IgA barrier and are absorbed as nutrients.

  • When All’s NOT GOOD

They say feed the system for the system to serve you better. Malnutrition can cause the enterocyte cells to not function properly, which may lead to the absorption of whole proteins. One whole protein can damage the entire gut system and functioning and cause gut-associated lymphoid tissue (GALT).

This condition can prevent the body’s natural immune response to a foreign protein. In the case of food allergies, the immune response fails to function and an adverse response (immune hypersensitivity) is generated.

So every time your dog ends up consuming the food containing the allergen or protein, the immune hypersensitivity reaction keeps increasing. The mast cells in your dog’s body release histamine. If the histamine is released beyond a certain level, it can cause allergy associated symptoms like itchy skin, chronic skin disease, diarrhea, etc.

Long-Term Effects

The long term effects of dog food allergies can cause chronic disorders like weakening of the immune system, severe skin conditions and overall poor quality of life. Your dog will always look pale and non-energetic, and will barely have any immunity to fight against diseases.Sever Skin Conditions during dog food allergy

Dog food allergies are not necessarily fatal and can be treated if you consult a vet. It is a serious concern for your dog to have him suffering from itchy skin and rashes. They may also show changes in behavior which is bound to affect your daily routine with him.

Diagnosing the symptoms and causative allergen helps prevent long-term effects like overall deterioration in health and quality of life.


In order for you to diagnose if your dog is suffering from a food allergy, consider showing him to a vet or check for symptoms which may help you rule out a few possibilities. Initially, it very important to identify the type of allergy, whether food-related or environmental.

Environmental allergies are more prevalent and lead to skin reactions. These can be tested by conducting intradermal and blood tests. But if your dog is showing gastrointestinal symptoms and falls ill off the season, then these are possible symptoms of your dog having a food allergy. Food allergy can be identified using the following methods listed below:

  • Elimination Diet

This is a food trial based method wherein you feed your dog a novel combination of protein and carbohydrates like fish and potato. This is a well known and reliable way to diagnose food allergy in dogs. It implies feeding something entirely new, involving basic ingredients without any additional flavors or additives.

The food has to be novel and not have been tried before. It is best to be prepared homemade as it would be more pure and reliable. These diets are commercially available too.Alter your dog's diet to detect the possible allergen While your pet follows the elimination diet regimen, avoid giving any treats or food containing flavors and additives. This regimen can last for 8-12 weeks. Post which, try feeding the potential or suspected allergen or dog food containing the allergen. If your dog has a breakout or shows an extreme response, that means he’s sensitive to that protein.

Certain dog owners feel that continuing with the elimination diet regimen is sufficient, and there is no need to detect the actual allergen. Although, once the course is over, you must try a few food items like a case of trial and error, in cycles, to check what suits and what does not suit your dog.

  • Other Common Diagnosis

Besides the elimination diet, rapid detection can be done using various diagnostic tests.

    • Blood tests: These are not very accurate and still under development for detecting new food allergies.
    • Skin Tests: This is a dermatological test. The test makes use of the potential allergen/protein and can be mixed with petroleum jelly to apply as a patch on the skin. After two days, if there is any redness or swelling observed, your dog is allergic to that protein. This is considered to be more reliable than blood tests but not very accurate.


The first and foremost step to be taken while treating a dog food allergy is to show your dog to the vet. The vet may suggest you carry out trials with various diets and check which type suits your dog best and helps in recovery.

It is important to identify which food type or protein is causing allergic responses and which food is safe for your dog to consume. Generally, a change in diet is sufficient to cure effects due to food allergies.

  • Diet

Treatment by improving your dog’s diet is purely experimental and requires an observation period. It is best to consult a vet as they would suggest a suitable protein in combination with a carbohydrate to check the reaction on your pet and to what extent it suits your pet. Below is a list of diets that are tried and tested on dogs suffering from allergies.

    • Low ingredient diet

Also called the limited ingredient diet, it barely contains any ingredients which makes it easier to identify the specific allergen rather than having to choose from a range of components in dog food. These dog diets are available commercially over the counter and do not require veterinary consultation.

    • Hypoallergenic Diet

These are specialized dog foods prescribed by vets and are either available online or at any local pet store. Hypoallergenic dog meals are made by breaking down massive protein molecules to their smallest amino acids which makes it easier for your pet to digest it.

That ways, the allergen is made almost invisible and the dog’s system continues to absorb amino acids from the hypoallergenic diet.

    • Homemade Diet

These dog foods are considered as a part of the elimination diet wherein various ingredients are tried and tested for potential allergies and intolerances. The owner is well aware of the ingredients present in the diet as he curates it all by himself. Preparation may require time and effort.

These diets are simple and easy to digest by your pet. Although, they may lack the most essential nutrients and components and may lead to deficiencies in the long run.

    • Vegan Diet

Vegan diets are a good alternative to meat. If you completely plan to eliminate meat protein sources, then vegan diets are a convenient option. Although they may involve a lot of vegetables, which also have proteins. Worse case, these proteins can also be potential allergens.

Commercially available vegan dog meals are found to be deficient in providing nutrition. These are only gaining prevalence amongst users but are not very effective for treating allergies.

  • Medications

The commonly used medicines for treating dog food allergies are anti-histamines or cream for topical application in case of skin infections. Before starting any course of medication or remedy, make sure to consult a vet. Antibiotics and antifungals like Cephalexin and Ketoconazole can help in treating secondary infectious cases temporarily.

Antihistamines are effective in reducing itching due to allergy. Anti-itching shampoos and lotions are also commercially available for regular use to treat and prevent allergies.


Dog food allergies are chronic and can have long-term effects on your pooch. This may end up causing them discomfort and a general deterioration in their health and habits. There are chances that once treated, these allergies might reoccur. So what can be done to keep allergies at bay? Read to find out.

  • Switch Diets

If your dog has developed an intolerance to a particular protein or a type of dog food, it is advisable to switch to a diet with a different protein source having various other ingredients and different percent composition of carbohydrates and fats. They do not necessarily have to be very minimalistic or have a limited range of ingredients.

  • Things to Check in Dog Food

    Before purchasing any of the dog food make sure that you consider at least the following factors:

    • Brand

Good quality and trusted brands are reliable and maintain transparency when it comes to detailing about the ingredients. There are specific dog foods that are available especially for dogs who are prone to allergies. These are specially formulated with a selected number of ingredients.

Although, while purchasing these types of food, it is advisable to rely on a brand that promises trust and good dog health and nutrition.

    • Ingredients and Additives 

Always check the label for the list of ingredients and additives. Certain dog food brands do not mention additional ingredients in spite of being a limited ingredient diet. These may contain potential allergens, food colors, and additives.

    • Quality and Freshness

The processing and preparation of the dog food also matter in determining the quality and freshness. Big batch cooking involving excessive machinery can cause contamination which deteriorates the quality and freshness of dog food.

Food cooked in small batches with limited human-grade ingredients and no artificial fillers is safer and better for your pup. In this way, you are also well aware of what your dog is consuming.


How common are dog food allergies?

Most of the allergies that happen in dogs are due to food. About ten percent of allergy cases are food allergies. Sometimes, it is misunderstood for food intolerance which is very different from food allergies.

What can trigger an allergy in my dog?

Allergies can be genetic although it happens only when your dog is exposed to the allergen. Typical ingredients of dog food like beef, dairy, meat, egg, fish, etc. contain proteins that can cause allergy. Dogs are usually found to be allergic to more than one thing.

Will changing my dog’s diet trigger a food allergy?

If your dog is allergic or sensitive to a particular ingredient in the diet, then it is advisable to eliminate the ingredient or replace it with an alternative. It may so happen that your dog has an allergy from the protein in the ingredient and a change in the diet should also involve a change in the potential allergen. Else it can trigger an adverse response.

Do food allergies develop suddenly or over time?

Your dog has to be sensitized to the food ingredient or allergen in order to develop an allergy. Dogs develop an allergy after progressive and gradual consumption of the allergen. They do not show a breakdown almost immediately. The best way to determine an allergen is to follow an elimination diet and then try to detect the actual allergen once the diet regimen is over.

Is homemade or cooked food better than giving your dog a commercial raw diet?

Homemade food is safe and we are well aware of the ingredients that go into it. Although, it is a hassle to prepare and is usually deficient of one or two essential nutrients and components. Cooked food is a good option, with the only difference that the structure of the proteins in the food will change as compared to their raw form.

The changed structure may or may not suit certain dogs. You can choose to provide a cooked or raw diet, whatever suits your dog best.

Final Note

When you notice your dog behaving or feeling unlikely, there are almost certain chances that it may be due to a food allergy or environmental allergy. Food allergy is caused due to a protein that is present in the most common ingredients found in dog food. These generally include beef, meat, chicken, fish, eggs, soy, cornmeal, etc.

Although food allergies do not get fatal, they deteriorate your dog’s overall health and activity levels. Therefore, getting it diagnosed at the earliest by consulting a vet and applying various combinations of elimination diets is the best method of detecting an allergen.

While choosing dog foods, it is very important to check the quality and list of ingredients. Avoid exposing your dog to any additives or artificial flavors that may have potential allergens.

Keep your dog’s diet simple and rich in nutrients to keep your pet’s immunity going strong and healthy for ages.