Adverse Food Reaction in Pets

As logic would go, feeding your dog or cat a high-quality, premium pet food would ensure their nutritional needs are met and they would thrive and live a long and healthy life. This is every pet owner’s objective for their beloved pet. However, some pets – both dogs and cats – can experience what is called an adverse food reaction. In this article, we’ll explore what adverse food reactions are, what causes them, when to take your pet to the vet, and how adverse food reactions are diagnosed and treated. 

If you think your pet is experiencing an adverse food reaction, this article may offer clarity on your pet’s condition.

What is an adverse food reaction?

When your pet eats their food and it causes an abnormal response in their body, we call this adverse food reaction (AFR). One or more of the ingredients in their food causes uncomfortable symptoms indicating that something is wrong. The two most common sets of symptoms show up on their skin (dermatological symptoms) and in their tummies (gastrointestinal symptoms).

What are the symptoms of adverse food reaction?

Dogs and cats present the symptoms of AFR a little differently. 

Symptoms in dogs

In dogs, their skin symptoms can include:
•    itching
•    rashes
•    skin infections
•    thickening and pigmentation of the skin
•    alopecia (hair loss)

Dogs’ gastrointestinal symptoms can include:
•    abdominal pain
•    diarrhoea
•    vomiting
•    borborygmi (tummy gurgling)

Rare symptoms may include the following:
•    head and neck swelling
•    hives (itchy, raised welts on the skin)
•    life-threatening anaphylaxis (drop in blood pressure; narrowed airways, which affect breathing)

Symptoms in cats

Cats’ skin symptoms can include:
•    itchiness (especially around the head, ears and on the neck)
•    pulling out their hair (due to itchiness)
•    bald spots
•    rashes
•    skin infections

Cats’ gastrointestinal symptoms can include:
•    abdominal pain
•    diarrhoea
•    vomiting
•    borborygmi (tummy gurgling)

Rarer symptoms in cats can include:
•    ear infections
•    eosinophilic plaques (raised wounds on the skin, nose or lips)
•    wheals
•    conjunctivitis

What causes adverse food reactions?

There are two different conditions that can cause your pet to have an adverse food reaction:
•    food allergies
•    food intolerance

The symptoms for both conditions are the same, but the mechanisms by which they develop are different. When your pet has a food allergy, their own immune system is triggered by an ingredient or protein (or many of them), which then reacts in a way that causes their physical symptoms. Instead of seeing the ingredient as beneficial, their immune system sees it as an invasive threat and subsequently attacks it, resulting in any of the above dermatological or gastrointestinal symptoms.

Common food allergens in dogs include beef, gluten and dairy; while cats are most commonly allergic to beef, dairy and fish. Food allergies in pets can pop up at any time in their lives – even if they’ve been healthy all along. If they’ve been diagnosed with one food allergy, they can also suddenly develop a different food allergy at any time.

If your pet has a food intolerance, it’s an abnormal reaction to a variety of ingredients or even contaminants in the food. Many dogs and especially cats are lactose intolerant, so giving them any dairy can cause mild to severe tummy trouble – this is a good example of food intolerance as an AFR. They may have food intolerances to various proteins and carbohydrates, but also to contaminants like fungi and bacteria, as well as to food preservatives, colourants and flavouring that may be added to pet food.

How are adverse food reactions identified?

Unfortunately for pets and pet owners, testing methods like blood tests, serology and intradermal skin prick tests cannot accurately detect a food allergy, so your best bet is with a food elimination trial. The vet will recommend a prescription diet consisting of one protein and one carbohydrate. Hydrolysed proteins may also be present, which are proteins that have been reduced into particles too small to cause the body to react. A prescription diet also does not contain many of the preservatives and additives in commercial pet food, known to cause a reaction.

Your pet will need to be fed exclusively on the prescription diet for eight to 12 weeks. It is critically important to the diagnosis that there be no deviation from the prescription diet – no snacks, table scraps, treats or supplements. After this time, the vet will be able to see if the symptoms have cleared up. When you reintroduce your pet’s original food and they have a flare-up of symptoms again, your vet will confirm that your pet’s symptoms are indeed from an AFR.

How are adverse food reactions treated?

When the vet has confirmed that your pet does indeed have an adverse food reaction, your pet’s best bet for living a healthy life is to avoid the food that is making them sick. Fortunately, there are many pet food options on the market that cater to pets with AFRs, such as protein diets with carefully selected ingredients that don’t contain any of the common allergens. There are also those diets that contain hydrolysed proteins, which are distilled down to a form that should not cause any adverse reactions.

A word on nutritional treatments for AFR pets

Home-cooked meals

Some pet owners are prepared to serve up home-cooked meals comprising novel proteins. While this may seem like the healthiest option and could technically not trigger an AFR, this type of diet does not offer your pet balanced, complete nutrition. Home-cooked meals – while filled with love and good intentions – are often too low in essential fatty acids, vitamins and minerals. If you want to feed your pet home-cooked meals, this must be done in consultation with a veterinary nutritionist who can determine the right levels of vitamins, minerals, omegas 3 and 6, and other nutrients required for your pet’s health and wellbeing.

Commercial prescription diets

Commercial pet food diets are designed to meet all of your pet’s nutritional needs; and for those pets with AFRs, there are scientifically developed diets containing the right blend of additional or alternative ingredients to meet their needs and avoid allergic or intolerant reactions.

Commercial pet shop diets

Some commercial over-the-counter pet diets make claims about being hypoallergenic, yet traces of allergens can still be found in their food. This happens when the pet food factories don’t have measures in place to prevent contamination from regular pet food, which is made in the same facility. 

Based on your pet’s needs, the vet will recommend a prescription diet for your food-sensitive pet, and it’s in your pet’s best interest to follow the vet’s recommendation.

The long road to health

The food elimination trial can be a tricky process – just one step in the long road to correctly identifying, isolating and treating your pet’s adverse food reaction. No pet owner wants to see their pet in distress or decline, so it’s best to work closely with the vet, keep an eye on your pet’s diet, symptoms and progress, and follow the vet’s advice and guidance on your pet’s health and wellbeing.

© 2023 Vetwebsites – The Code Company Trading (Pty) Ltd

Scroll to Top