What to feed cat with food allergy

It may take months or years before your cat develops an allergic response to a specific food. However, once she’s allergic, she will almost always own a negative reaction to that food. Allergic reactions are most commonly associated with protein sources – generally the meat in your cat’s food.

Food: The most common causes of food allergies and food intolerance in cats are beef, milk products and fish.

Damage: Inflammation, infection, surgery and some medications can damage the digestive system and may lead to food allergies or food intolerance.

Age: Food allergies and food intolerance can happen at any age.

Breed: Some cat breeds appear more likely to develop food allergies or food intolerance, including Siamese cats.

Food Allergies

Unlike an intolerance, a food allergy can affect both the gut and the skin, and is an abnormal immune response to an otherwise safe ingredient.

Cat allergies are generally to a protein source such as fish or chicken. Cats most commonly develop food allergies between the ages of 2 and 6, and must be repeatedly exposed to the offending allergen (for example, by eating it every day) to develop signs of a problem. Those signs can include vomiting, diarrhea, flatulence, loss of appetite, itchy skin, hair loss or reddened skin.

Believe it or not, grains such as corn are not the most common cause of food allergies in cats. If you’ve ever wrongly suspected your kitty may be reacting to an ingredient, however, you’re not alone: Veterinary Pratice News writes that most «food allergies» are misdiagnosed by concerned pet parents during a simple stomach upset.

According to Tufts University Cummings Veterinary Medical Middle, the most common reported allergies for cats and dogs are chicken, beef, dairy, and eggs (and fish for cats).

Food Intolerance

There are numerous things inside and exterior the cat gastrointestinal system that can cause a cat’s sensitive stomach, including food intolerance and food allergies. Though they sound similar, these two issues are not the same thing.

Food intolerance can happen in cats of every ages, and it can be caused by food poisoning from spoiled food your cat mistakenly ate or a sensitivity to a certain ingredient.

A sensitive stomach from food intolerance can also happen when a cat lacks an enzyme needed to fully digest a certain food, has irritable bowel syndrome or is stressed.

Many things can cause stress in a cat, including boarding, moving, adding a new pet to the family, dental disease or pain from arthritis. If you notice that your cat is vomiting or has diarrhea and you suspect she may own a sensitive stomach, don’t change her food just yet. There may be another medical reason for her upsets.

If her vomiting or diarrhea is severe or doesn’t clear up within 24 hours, it is time to get your veterinarian involved.

Easily Digestible Foods

Some cats with sensitive stomachs may need a change in food. Your cat may not need to avoid eating a certain ingredient, but her type or formula of food could be part of her intolerance problem. One solution for a stressed kitty with digestive symptoms is switch to an easily digestible food.

Digestibility, in pet food research terms, describes how easily a cat or dog can process and get essential nutrients from what they eat. According to the Cameron County Society for the Prevention of Cruelty to Animals, the factors that most influence digestibility are the ingredients, ingredient quality and processing methods used in making a food.

Foods for a sensitive stomach, love certainHill’s Presciption Diet® cat foods, include a combination of soluble and insoluble fibers, minerals and healthy fats to make them nutritious yet tender on your cat’s digestive system.

What to Do About Food Allergies

If you or your vet suspect a food allergy, then it may be time to attempt a hypoallergenic cat food. Enquire your vet to give you their best recommendations; the only way to accurately diagnose a food allergy is with a strict diet trial.

If you are thinking about heading below to the pet store and picking up some new food yourself instead of visiting the vet, wait a minute.

This is a common pet parent error when dealing with a cat’s sensitive stomach. Switching diets around will only confound the issue and make it harder for your vet to figure out the correct way to treat your kitty’s dietary woes.

Most over-the-counter diets are also not considered hypoallergenic. Even if a food is labeled «fish,» there can still be trace amounts of chicken, beef or eggs present because numerous types of pet foods are made in the same facilities with the same equipment. Just love a plain chocolate bar often warns «may contain traces of peanuts,» cross-contamination can affect pet food manufacturing similarly.

Proper food trials will take about 10–12 weeks in which your cat must eat her new food and nothing else — no treats, no scrambled eggs and no kitty toothpaste, unless it is cleared by your vet.

If your cat has a true food allergy, then any sensitive stomach issues should clear up in 2 to 4 weeks. External symptoms love itchy skin will take longer to resolve. A minimum 12-week meal trial is recommended for skin issues because it takes that endless for a cat to grow a new outer layer of skin cells (human skin takes about 39 days to turn over, according to Trade Insider). If you own been religious about your diet trial but your cat is still having problems, then the issue isn’t a food allergy and it’s time to check for other conditions.

What Are Hypoallergenic Diets?

Hypoallergenic therapeutic diets are specially formulated and produced to be free of contaminating allergens that might set your cat’s sensitive stomach on edge.

Do yourself a favor and get the cat food that your vet recommends correct from the start, and follow every diet trial instructions carefully. If your cat sneaks anything else to eat, then you own to start the trial over again. Yes, you may spend more on this food versus a grocery store brand, but remember: you are investing in your pet’s health, and in this case, food really is medicine.

A truly hypoallergenic cat food uses hydrolyzed proteins, meaning that they own been broken below so far that your cat’s body doesn’t recognize the allergen allowing your cat to process the food as intended. Another solution is to use a food with a novel protein love duck or venison, as these are protein sources that your cat might not normally be exposed to in other foods.

If giving your cat treats is an significant part of her training, there are also hypoallergenic treats, but always check with your vet first. No matter the cause of your cat’s tummy woes, your vet can assist you discover a way to soothe them.

Most common culprits

Because food hypersensitivity can be the manifestation of a type I, III or IV hypersensitivity reaction, the onset of clinical signs can range from minutes to days after ingestion of the offending allergen.

In people, the allergen generally has a molecular weight above 12,000 daltons, although this has not been confirmed in domestic animals, where the offending allergen may be smaller.

A number of studies published over the years own listed the most common food allergens in dogs and cats. Summarizing these reports has led numerous dermatologists to conclude that animals own the potential to become allergic to any food stuff to which they are exposed, especially proteins. In a 1996 report in dogs in the United States, the most common allergens were beef, chicken, chicken egg, cow milk, wheat, soy and corn.1 In this report, 80 percent of the dogs reacted to just one or two items, although there are reports of dogs allergic to as numerous as nine food items.

Additional published reports list fish, rice and potato as foods known to cause adverse reactions. The food items most commonly known to cause ARF in cats include chicken, fish and dairy products. A few minutes spent reading the ingredient labels of most commercial cat foods will show these are the most common ingredients used in formulating the diets.

One common misconception of clients and numerous veterinarians is that food allergy is more likely to develop only after a recent diet change.

In fact, when food allergies develop, the offending allergen has often been fed for more than two years, and some patients will eat the same protein for numerous years before the allergy develops.

Further complicating the workup of a patient with a suspected food allergy is the recognition that some patients will own cross reactions between related food ingredients. This phenomenon is well recognized in human medicine as well. Examples include patients allergic to chicken who will not tolerate duck or turkey. Some patients allergic to beef will cross-react or show clinical signs when exposed to other ruminants, such as lamb or venison.

Fortunately, not every patients with food allergies will own cross reactions, but some will.

Food hypersensitivity in dogs

No age or sex predisposition is known to exist regarding the development of food allergy in dogs, but as numerous as 50 percent of patients with food allergies may exhibit clinical signs at less than 1 year of age. The so-called allergic breeds such as Cocker spaniels, Springer spaniels, Labrador retrievers, miniature schnauzers, Shar Peis, West Highland white terriers, Wheaten terriers, German shepherds and Golden retrievers may own a higher rate of food allergy.

I own seen a higher rate of food allergy in three dog breeds—German shepherds, Rhodesian ridgebacks and Shar Peis.

Clinical signs vary, but nonseasonal pruritus, otitis and dermatitis are frequently seen. Sometimes the clinical signs are as simple (or vague) as recurring pyoderma or a nondescript keratinization disorder (seborrhea). Food allergy should always be considered in any patient with recurring urticaria, and eosinophilic vasculitis has also been associated with ARF.

In general, the clinical signs of food allergy are nonseasonal, although they could be episodic if they are due to sporadic treat istration. It is also possible for the effects of a food allergy to be low or subclinical (below a pruritic threshold) and only happen with the addition of environmental allergens will the patient flare.

Any dog with a nonseasonal pruritic dermatosis should own food allergy ruled out as a contributing cause of the skin disease.

Several other clues may lift your index of suspicion that a patient is suffering from a food allergy. One is the pattern of skin disease. Food allergies are known to commonly affect the "ears and rears" of the patient.

What to feed cat with food allergy

Another potentially useful clue is the response to corticosteroids. Atopic dermatitis is generally responsive to corticosteroids at anti-inflammatory doses. While some patients with a food allergy will be extremely responsive to corticosteroids, some will not, and when the pruritus is not corticosteroid-responsive, food allergy should be considered.

Nearly half my patients own gastrointestinal manifestations of their ARF. Dramatic gastrointestinal signs include vomiting and diarrhea, but they may be as subtle as flatulence or frequent (more than twice a day) bowel movements.2 Rarely reported clinical signs of ARF include seizures and respiratory signs such as bronchitis, rhinitis and chronic obstructive pulmonary disease,3 every of which I own seen.

Contributor Bio

Dr. Sarah Wooten

Dr. Sarah Wooten graduated from UC Davis School of Veterinary Medicine in 2002. A member of the American Society of Veterinary Journalists, Dr. Wooten divides her professional time between little animal practice in Greeley, Colorado, public speaking on associate issues, leadership, and client communication, and writing. She enjoys camping with her family, skiing, SCUBA, and participating in triathlons.

Food hypersensitivity, food intolerance and other adverse reactions to food (ARF) cause a myriad of effects on several diverse systems of the body, with the integument and digestive systems being most commonly affected.

This two-part article series provides insight into how ARF affects the skin in dogs and cats and how to definitely diagnose and manage patients with food allergies.

Feline food allergy

No age or sex predisposition has been reported or recognized in cats with food allergies. One study in cats with food allergies reported the offending allergen had been fed for more than two years on average.4 Siamese and Siamese crosses may be predisposed to food hypersensitivity. The classic or hallmark clinical sign of food allergy in cats is pruritus, especially of the head. Cats may also exhibit self-induced alopecia or any manifestation of the eosinophilic granuloma complicated.

Definite diagnosis of an ARF requies an elimination diet trial.

What to feed cat with food allergy

Part 2 of this two-part series will cover how to conduct a successful trial and assist patients get rid of the itch once and for every.

Dr. Lewis sees dermatology patients in California, Azrizona, Nebraska, New Mexico and Washington. In 1991, he established Dermatology for Animals, PC.



What to feed cat with food allergy

Jeffers JG, Meyer EK, Sosis EJ. Responses of dogs with food allergies to single-ingredient dietary provocation.

What to feed cat with food allergy

J Am Vet Med Assoc 1996;209(3):608-611.

2. Paterson S. Food hypersensitivity in 20 dogs with skin and gastrointestinal signs. J Little Anim Pract 1995;36(12):529-534.

3. White SD. Food allergy in dogs. Compend Contin Educ Pract Vet 1998;20:261-268.

4. White SD, Sequoia D. Food hypersensitivity in cats: 14 cases (1982-1987). J Am Vet Med Assoc 1989;194(5):692-695.

The term cutaneous adverse food reaction (food allergy) is often used to define the food-triggered clinical syndrome of allergic dermatitis, gastrointestinal (GI) signs or both.

Food allergies may be responsible for chronic skin and ear disease in both cats and dogs.

Potential allergens can include protein sources (e.g. chicken, turkey, beef, lamb, soy, dairy, eggs) or carbohydrate sources (e.g. corn, rice, barley, wheat). Some pets can own more than one food allergy. Food allergies often start in pets younger than 1 or older than 7 years of age, but they can be acquired at any time, even when a pet has been eating the same food for months to years.

What does food allergy glance like?

Food-allergic animals generally own nonseasonal pruritus because the source of the problem does not change with the weather or seasons.

About 20% of food-allergic pets also own GI signs such as flatulence, vomiting, diarrhea, noisy intestinal sounds, or defecating more than four to five times a day. Dogs may scratch their face, ears, feet, groin or anal area or develop recurrent skin or ear infections (Figure 1). A frequent presentation includes licking at the anal area in addition to problems with the ears-this is why the condition is often referred to as one that affects “ears and rears.” Cats may overgroom certain areas of the body or the whole body, exhibit intense itching at the face or neck, or develop ear infections.

Figure 1.

Skin infections in a food-allergic cat (top) and dog (bottom). Images courtesy of Judy Seltzer, BVetMed, MRCVS, DACVDThe onset of food allergy can be slow and gradual or more sudden. Clinical signs often continue to progress as endless as the offending allergen is fed. It can take several weeks to months for clinical signs to resolve once the allergenic agent is removed from the animal's diet. Up to 30% of food-allergic pets may own other allergies, such as a flea allergy dermatitis or atopy (environmental allergies). About 50% of food-allergic dogs will not reply favorably to steroids.

Diagnosis and treatment of food allergy

The only precise way to diagnose an animal with a food allergy is to remove all of the currently fed foods and start a strict elimination diet trial.

Available blood and saliva tests are not dependable for diagnosing food allergies in cats and dogs, and skin testing has also been found to be ineffective.

An elimination diet consists of a prescribed home-cooked or prescription therapeutic diet that contains a unique protein and carbohydrate source to which the animal has not previously been exposed. The most common novel protein diets include rabbit and potato, venison and potato, and kangaroo and oats. Numerous fish and lamb diets are no longer considered novel as these ingredients are more commonly used in over-the-counter (OTC) diets.

Another option is to use a hydrolyzed (low-molecular-weight) diet, also available by prescription.

These diets are composed of common ingredients (such as chicken and soy) that own been molecularly altered to be under the allergenic threshold. This alteration prevents the animal's immune system from recognizing the food.

Oh, no, you didn't

Simply changing from one brand of pet food to another does not constitute an allergy diet trial. Several OTC “allergy” or “limited-ingredient” diets are now available in pet stores and online, but they are not always as pure as they claim to be or may own hidden ingredients.

Some pets with food allergies will not get better on a pet store diet.

A little percentage of truly food-allergic animals remain undiagnosed with commercially prepared diets and need to be trialed with a home-cooked diet.

Home-cooked diets. Examples of proteins used in home-cooked diets are tilapia, salmon, duck, rabbit, pork or pinto beans, generally mixed with sweet potatoes, oats, quinoa or barley. A home-cooked diet should be nutritionally balanced. Therefore, recommend that the client consult with a board-certified nutritionist before feeding a home-cooked diet.

Nutritionists are also extremely helpful when an animal has a concurrent disease, such as urinary tract infection, history of bladder stones or irritable bowel disease, and they can work with the primary veterinarian or dermatologist to formulate an appropriate diet. Websites including balanceit.com and raynenutrition.com own also been helpful in formulating home-cooked diets for a trial.

Therapeutic diets. Veterinary dermatologists often prescribe therapeutic diets from Royal Canin, Hill's and Purina for use in elimination trials.

What to feed cat with food allergy

In addition, Rayne Clinical Nutrition makes rabbit, kangaroo and pork diets for dogs and cats that are less processed than dry kibble or canned foods. Selecting a diet will depend on your patient's diet history. Furthermore, some cats and dogs will require a wet food to assist ister medications, and some owners are adamant about having treats to feed their pet. Knowing the needs of your patient and client will assist in choosing the most appropriate diet for your patient.

Did we mention elimination diet trials are strict?

Emphasizing to clients that absolutely no other food products or treats should be given during an elimination diet trial is imperative.

The pet should be allowed to consume only the prescribed diet, associated treats and water. Pets in an elimination trial cannot have:

Table food

Rawhides, pig ears, bones or other chew toys made with animal products

Supplemental fatty acids

Parasite preventives, medications or toothpastes with added flavor

Treats used to ister medications (e.g. peanut butter, cream cheese, lunch meat, pill pockets).

Regardless of which elimination diet is selected, it should be introduced gradually over a five- to seven-day period.

This is extremely significant as some animals may develop GI problems if their diet is changed suddenly. Most pets adapt to the new diet well, but some need time to adjust. If the pet doesn't adjust to the new diet within a week or two or refuses multiple therapeutic diets, a home-cooked diet can be formulated with the assist of a veterinary nutritionist.

What to feed cat with food allergy

To formulate the best possible plan for your patient, it is also significant to take into consideration challenges such as households with multiple pets or little children.

The elimination trial should continue for at least eight to 12 weeks and a minimum of one month beyond resolution of a skin infection. The pet should be rechecked frequently to assess the progress and results of the diet trial. Rechecks may be more frequent if the pet is being treated for an athletic infection.

If the pet has a food allergy, we expect to see at least a 50% reduction in licking, scratching, chewing or other dermatologic signs. This may happen within the first four weeks for some animals; in others the response may take up to 12 weeks.

Cats may need to be on the elimination diet for three to four months before a food allergy is confirmed.

The diet challenge

To prove that a food allergy is responsible for a pet's condition, a diet challenge is typically performed. This involves reintroducing the original diet, or ingredients from the original diet, to see if the pet has any reaction. In the food-allergic pet, clinical signs will generally worsen within hours to two weeks. If an adverse reaction occurs, resume the elimination diet exclusively.

Once the flare-up is resolved, reintroduce individual ingredients from the previous diet one at a time to identify the specific cause.

Beyond proving the food allergy diagnosis precise, a food challenge helps to determine which specific foods or treats should be avoided and to identify an OTC diet that the pet can tolerate. If we can determine the ingredient causing the problem, we can manage the condition by eliminating the offending food(s) from the pet's diet for life.

Keep in mind, however, that this may not always be possible. Some patients may need to remain on a therapeutic or home-cooked diet for life. Feeding a therapeutic diet long-term will not harm a pet because these diets are well balanced.

Therapeutic diets tend to be more expensive than OTC diets, however, and numerous owners prefer to feed a commercial diet.


As with other types of allergies, there is no cure for food allergy. What's more, animals can develop new food allergies over time. However, if a food allergy is the sole cause of a pet's skin or ear problems, identifying and eliminating the protein(s) or carbohydrate(s) causing the allergy may significantly increase the pet's quality of life and reduce or prevent skin and ear problems in the future.

As noted earlier, pets with an allergy to food ingredients are at higher risk for developing other allergies such as atopic dermatitis or flea allergy dermatitis.

To hold under an animal's itch threshold, every food-allergic pets should be maintained with strict flea control and monitored for secondary skin infections and itching.

Dr. Judy Seltzer graduated from the Royal Veterinary College in London and completed her residency in dermatology at the University of Florida. She has been working in her home state of New York since 2009, currently at BluePearl Veterinary Partners in New York City.

She and her husband own a little girl and four cats and enjoy traveling, drop festivals, winter activities and dining out.

What are food allergies or food intolerance?

Food allergies / intolerance are caused by a reaction to a specific ingredient, which is generally a protein. Sometimes referred to as an ‘adverse reaction to food,’ it is defined as an abnormal response to a food or food additive. There are two classes of adverse reactions: those in which the immune system is involved (generally called food allergies); and those that happen without an immune component (generally called food intolerances).

Allergies may final a lifetime so the ingredient must be permanently removed from your cat’s food.