By Dr Daisy May MRCVS BVSc, Veterinary Surgeon

It’s that time of year again: lawn furniture is dragged from sheds across the country. Decks are dusted off. Sunhats donned. And – with increased time spent outdoors, as well as increased pollen counts – our dogs are getting allergies. As a practicing and licensed vet, canine allergies are one of the most common (and most frustrating!) issues that I see affecting man’s best friend…and never more so than in summer.

In reality the above example does simplify things a little, since in fact (just like us), our dogs can be allergic to almost anything. Canine allergies “work” similarly to human allergies: the dog’s immune system mistakenly identifies harmless foreign molecules – such as pollen or dust mites on the skin surface, or specific protein molecules in your pet’s food – as being a threat, and an inflammatory cascade of symptoms results.

While human allergy symptoms frequently include the runny nose, stuffy sinuses and sneezing that every hay fever sufferer will be all too familiar with, dog allergies more commonly rear their ugly heads with itchiness and/or gastrointestinal upset. Let’s take a closer look at what you might notice.

What Happens When Dogs get Allergies: Signs and Symptoms

Broadly speaking, when dogs get allergies, they can be categorized as either being allergic to food, or being allergic to things in the environment (although since nature is never simple, there is overlap: some unlucky hounds are allergic to both food and environmental allergens!)

Food allergies in dogs are actually less common than the environmental type, and tend to present at an earlier age, with some combination of vomiting, diarrhea, appetite problems and/or itchy skin. Food allergic dogs will often tend to get especially itchy around the muzzle and the anus i.e., areas that touch the food on its way in or out! These dogs will often rub their face (or their butts) on furniture or the floor, especially after eating or umm, answering nature’s call.

Dogs with allergies to things in the environment also exhibit itchy skin. In this case it’s usually the feet, ears, armpits and groin that are worst affected. Sometimes a rash will be present, but usually the itch comes first, and the rash comes later, if at all. Allergic dogs are frequently also very prone to having super waxy ears, or getting recurrent ear infections. In fact, for some allergic dogs, ear problems are the only sign of the allergy! So, overall it’s a very different ballgame from human allergies. 

Which Dogs get Allergies?

Figures vary widely depending on who you ask, but most studies report that between 3-15% of all dogs get allergies of the environmental type. In my experience as a vet, “1 in 10 dogs” is probably the figure I hear cited most commonly, and seems to be about right.

Interestingly, multiple studies have shown that Golden and Labrador Retrievers, West Highland Terriers, German Shepherds and French Bulldogs are more likely to develop environmental skin allergies compared to other breeds [2]…so if you own one of these breeds, be on the watch, especially around summer when these allergies are most likely to be flaring up!

When it comes to food allergies, German Shepherds, Westies and Retrievers once again get an unfair share. One study actually found that 40% of the surveyed population of dogs with food allergies fell into one of these breeds [4]. That’s nearly half!

These breed patterns strongly suggest that genetics are a really important factor when it comes to deciding which dogs get allergies and which don’t. 

What do Dogs get Allergies to?

Something I’ve always found extremely interesting as a vet (and please bear with me, I promise it’s relevant!) is the popularity of grain free foods for dogs. This fancy chow is everywhere! Yet as a certified dog-tor, I’m here to tell you that according to science, canine grain allergies are actually extremely uncommon. In reality, hypersensitivities to corn, rice, barley, rye or oats are basically unheard of in dogs. Our four legged pals can get wheat allergy, but it’s reported that only around 1 in 10,000 dogs are affected [1].

So, if our dogs aren’t allergic to grains, what are they allergic to?

In terms of food allergies, studies have identified that for dogs living in North America, Europe or Australia, the three most common offenders are beef, dairy products and chicken [4]. For environmental allergies in dogs, fleas, house dust mites, fungal spores and pollen (from grass, trees, weeds etc) seem to be common offenders [3].

This brings us nicely to touch upon the subject of seasonal versus non-seasonal allergies in dogs. If your dog’s allergy symptoms are seasonal, they’re probably reacting to allergens such as grass or tree pollen. On the flip side, if your pup is unlucky enough to experience allergy symptoms year round, then they are more likely allergic to things found inside the home such as house dust mites, or to food. 

Conclusion

By now it should be clear that dogs do indeed get allergies. If your pup is rolling around and rubbing themself on furniture like it’s the latest dance craze, shaking their head like a judgemental grandmother or sucking on their itchy paws like a lollipop…you may well have canine allergies to blame.

And believe me, if it’s bad enough that you’re noticing it daily, it’s not “a habit” (whatever Johnny in the pet shop or Sally at the groomers told you) – it’s itch. In many cases, a veritable inferno of itch. So please, don’t delay seeking veterinary attention for your pet if you notice signs consistent with an allergy. It may be frustrating living with a constantly scratching pooch, but I promise you, your dog is even more fed up with it. Let’s get them the help they need.

References

1. Beynen, A.C. (2020) ‘Gluten Proteins for Dogs’, Food Chemistry. Available at: https://www.researchgate.net/publication/342436279_Beynen_AC_2020_Gluten_ proteins_for_dogs (Accessed 30 July 2024).

2. Drechsler, Y., Dong, C., Clark, D.E. and Kaur, G. (2024) ‘Canine Atopic Dermatitis: Prevalence, Impact, and Management Strategies’, Vet Med (Auckl),
3. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10874193/ (Accessed 30 July 2024).

3. Mueller, R.S., Janda, J., Jensen-Jarolim, E., Rhyner, C. and Marti, E. ‘Allergens in veterinary medicine’, Allergy: European Journal of Allergy and Clinical

Immunology. Available at: https://onlinelibrary.wiley.com/doi/full/10.1111/all.12726 (Accessed 30 July 2024).

4. Valentine, B. (2020) ‘Review of critically appraised topics on adverse food reactions of companion animals’, The Canadian Veterinary Journal, 61(5). Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7156131/#:~:text=Almost%2040% 25%20of%20dogs%20with,CAFR%20in%20dogs%20and%20cats. (Accessed 30 July 2024).