Dog with skin condition possibly caused by a food allergy scratching with its hind leg..

Itching, scratching, vomiting, diarrhoea. Food allergies are distressing for both you and your dog. It’s awful to watch them in so much discomfort, and you feel totally helpless.

Vets often recommend an elimination diet to diagnose allergies and help identify the cause. This guide will help you understand what that means, how to carry out an elimination diet, and how natural treats can help keep the yum in their tums!


What is a Canine Food Allergy, and What Does it Look Like?

A food allergy is an immune response to a substance or ingredient in your dog’s diet. Although the terms “allergy” and “intolerance” to foods are often used to mean the same thing, in fact, they’re quite different. An intolerance is difficulty digesting certain substances and can result in tummy upsets. A food allergy in dogs occurs when a specific ingredient, usually a protein or (less commonly) a carbohydrate, triggers an immune response in them.

In many cases, food allergies result in itching (pruritus) and sore, red, and inflamed skin. They might scratch their face, ears, neck, groin or overgroom themselves until their skin is raw and painful.

Sore, red skin on dogs paw, caused by overgrooming possibly due to a food allergy

About 15% of food allergies also present with gastrointestinal issues, such as vomiting, diarrhoea, flatulence or a very rumbly tum.

Many dogs diagnosed with food allergies are also allergic to other environmental allergens, such as dust mites, grass, or fleas.

Your vet’s first line of treatment may be steroids to soothe the itch. However, if the skin condition is related to allergies, in many cases the steroids won’t help. You need to remove the allergen from their diet.


What are Common Food Allergens?

In reality, your dog could be allergic to any ingredient in their food and, as you can imagine, there are some weird and wacky things dogs have turned out to be allergic to. But the most common food allergies reported are to beef, dairy, chicken, lamb, wheat, and soy.

As commercial pet food becomes more sophisticated and includes more exotic ingredients, there is also an increase in allergies to other protein sources, which makes choosing a diet more difficult.


How Does a Vet Diagnose My Dog with a Food Allergy?

The only true way to diagnose a food allergy is with an elimination diet followed by food challenges. Although there are blood and saliva tests on the market that claim to be able to diagnose food allergies, these are not yet reliable enough and shouldn’t be used as a diagnostic tool.


What is an Elimination Diet?

An elimination diet reduces your dog’s diet to very minimal ingredients. These include protein and carbohydrate sources that your dog is unlikely to have encountered before or that it is unlikely to be allergic to. These are known as “novel” protein and carbohydrate sources.

You must stick to this diet very strictly over several weeks, even after the allergy symptoms have resolved. Then, gradually, you add ingredients back in until you identify one they are allergic to when symptoms begin to manifest again.

How Does an Elimination Diet Work, and What Foods Can I Feed My Allergic Dog?

There are three main options when it comes to choosing the type of diet to diagnose your dog’s food allergy, and your vet will be able to recommend a sensible choice for your dog’s specific case. You could use a novel home-cooked diet, a novel protein kibble-based diet, or a “hydrolysed” diet.


Home-cooked Meals

This is fast becoming the most popular option for owners, with the rise of raw and fresh dog food. Simple diets with few ingredients are best at this stage, but choosing your ingredients can be tricky. It’s easier if you’ve had your dog since it was a pup, as you might have more idea of what ingredients and flavours they’ve had in their lifetime.

Dog cooking a home-cooking elimination diet meal

Examples of novel protein sources might be rabbit, venison, or duck (some brave people even try kangaroo, but it’s not so easy to get hold of in the UK). You could pair these with a novel carbohydrate source such as sweet potato or peas.

The most important thing if you are cooking at home is to ensure the diet is balanced and your dog is still receiving the nutrition they need. Your best option would be to speak to a qualified pet nutritionist for advice.


Kibble-based Novel Protein Diet

Many veterinary food manufacturers make specific novel protein source diets, which are available via your vet or online food retailer. These are specifically designed with allergies in mind and utilise a variety of novel protein sources so that there is something to cover most allergic bases. For example, Royal Canin have fish or duck options, and Hill’s Pet Nutrition diets contain either duck or salmon.

Elimination diet kibble dog food being measured into dog bowl


Hydrolysed Diets

This is another kibble-based option. In these diets, the protein and carbohydrate elements that may be allergens are hydrolysed. This means they are broken down either physically or using enzymes so that they are so small that the immune system won’t recognise them as an allergen, and therefore, there won’t be an immune reaction.


How Long Should My Dog Be on an Elimination Diet?

It is recommended that you try an elimination diet for an absolute minimum of 8 weeks, but ideally, at least 12 weeks, even if your dog’s symptoms improve (because that’s what we’re aiming for anyway).

Once your dog has been symptom-free for a few weeks and you’ve hit the 8 to 12-week mark, you can start the challenge part of the diet.


What is a Food Challenge and How Do I Do It?

Once your dog’s system has settled, they are ready for a food challenge. This is when you gradually add new ingredients to their diet to see how they respond.

Some vets recommend reintroducing their original diet, while others prefer to go ingredient by ingredient to pinpoint the allergen.

When you introduce a new ingredient, your dog may show allergic symptoms within a few hours, or it may take a couple of weeks.

If, after two weeks, there are no signs of a reaction, you can introduce another ingredient.

If your dog has a flare-up of their symptoms when an ingredient is introduced, remove it immediately and go back a step until symptoms have resolved. Eventually, you will have identified a selection of ingredients your dog is allergic to and, hopefully, plenty that they’re not.

Dog on elimination diet licking burger and saying “I’m just testing it”.

Many owners find the process long, arduous and nerve-wracking as they don’t want their dog, who now seems happy and comfortable, to flare up again. This is absolutely fine, and as long as the elimination diet they are on is healthy and balanced, there is no reason why they can’t stay on it.


Can My Dog Have Anything Else While They’re on Their Elimination Diet?

Ideally, your dog should only be having their elimination diet. You need to take care when considering anything else that goes into their mouth. Even worming medication may contain flavourings that have, for example, chicken in them.

Can I Give My Dog Treats if They’re on an Elimination Diet?

Treats are an important part of your dog’s life. They help build your bond with each other; they’re vital in training; and the right treats are a great source of mental stimulation for your dog.

If they’re on an elimination diet, most treats should be avoided. You can’t guarantee the contents of processed treats, as the UK labelling regulations mean manufacturers don’t have to divulge each protein source.

So processed, packaged treats are probably out.

However, natural, single-source protein treats could be a great option to support your dog. You know which proteins are safe to eat, so adding single-source protein treats means you are still managing their diet while giving them a tasty snack. Happy, waggy tails!


How Can Natural Dog Treats Support My Dog’s Elimination Diet?

Here at Treat Treehouse, we love funky, yummy treats, and we know how important it is to have something tasty to spoil your pooch with. That's what makes elimination diets so tough – you have to be so strict!

But if you’re home cooking or know which protein sources are safe for your dog, then perhaps natural treats could help. Your dog could have something yummy, something to chew, or a treat after training.


Natural dog treat, duck necks - elimination diet


All of our natural treats come with detailed nutritional information, and plenty of them are single-protein sources from meat sources that are low on the allergen scale and used in elimination diets. You can choose treats that fit your dog’s situation.


Which Natural Treats Might Support My Dog’s Elimination Diet?

As we said before, some common allergens are worth avoiding (unless you have ruled them out already). However, many of our treats are a single source of protein, and assuming you know your dog will not react to that protein, you could add these natural treats into their routine via your elimination diet.

Some suggestions are rabbit, venison, and duck. (Just be aware that not all of our sausages and slices are single protein sources). Sometimes, pork is an appropriate protein source, too. However, ensure you have completed a challenge with any new protein before including it in your dog’s routine.

We have a variety of single-source protein options, so why not make a Pick‘n’Mix box of lip-smackingly delicious snacks for your dog to work through?


Natural dog treat pick n mix box - elimination diet


Pick a few and discover their favourite!

Fill My Pick‘n’Mix Box

Luce Rawlings