What is the Difference Between Atopy and Allergy in Dogs?

Very often when our dogs suffer an allergy it is said to be atopic. So what does this mean? Is it the same thing as an allergy? The answer is not simply yes or no.

Atopy is the genetic predisposition of an dog to produce high quantities of IgE in response to allergens in the environment (pollens, house dust mites, moulds, cat dander, foods etc).  Genetic factors are very important in Atopy, as it can be passed down from generation to generation.  Atopy is silent; so atopic dogs do not necessarily display symptoms when they come across allergens. The only way to identify Atopy is through allergy tests which measure IgE for various allergens.  So Atopy is a condition for the development of allergy but is not itself allergy!

Allergy, in Vet terms, means that the dog develops symptoms upon contact with allergens to which he/she is sensitised.

So your dog needs to be atopic to become allergic but if he/she is atopic they will not necessarily progress to an allergic state (not all atopic dogs start developing allergy symptoms). It is not clear what causes atopic dogs to behave differently. It might be that some environmental factors added to atopy (the genetic predisposition to allergy) stimulate the progression towards allergy or, as suggested by some new research data; it might be that expressing allergy requires an atopic predisposition and also other inherited genetic factors not related to production of IgE.

A simple way to think of Atopy for dogs would be simply saying that the pet inhales an airborne allergen but instead of sneezing and sniffling, the pet gets itchy skin. In fact, the situation is probably far more complex. The allergen is not only inhaled but is in contact with the skin and it is no longer considered accurate to think of Atopy as an inhaled allergy. Exactly how we get from particles floating in the air to itching and scratching is not entirely understood but the important issue is that the allergen comes from the air.

Airborne particles (pollen, dander, etc.) are harmless to someone who is not allergic to them. Allergy develops in individuals who are genetically programmed to do so.

Breeds predisposed to develop Atopy include: Dalmatian, Golden retriever, West Highland white terrier, Shar Pei, Labrador retriever, Cairn terrier,  Lhasa Apso,  Shih Tzu,  Boxer, and  Pug.

Features of Atopy

There are many reasons for pets to itch: parasites, allergy to flea bites, food allergy, secondary infection and the list goes on. The following findings in the history and examination of the patient might lead to a diagnosis of atopy.  Atopy usually produces a seasonal itchiness though after several years, the duration of the itchy period extends. Finally, the pet is itchy nearly all year round.

Seasonality
In dogs, atopy usually produces a seasonal itchiness though after several years, the duration of the itchy period extends. Ultimately, the dog is itchy nearly all year round in 80% of cases. In cats, unfortunately, seasonality is not nearly as reliable a feature.

Young age of onset
Seasonal itchiness due to atopy tends to begin early in a pet’s life (between ages 1 and 3 years in 70% of dogs diagnosed with atopy). Food allergy tends to begin later, more like age 5 or 6 years in dogs. Age at which itching first manifests is not as reliable a sign in cats as in dogs.

If you think you dog is suffering from Atopy or an allergy, first we need to identify what is causing it. You can have tests done by your vet to determine the cause, but there are a few things we can do ourselves to help. Always feed your dog a high quality diet, as we find so many dogs improve within a few days when the feed is changed. Make sure your house is dust free and well ventilated, and that your dogs bed is kept clean.

At Dermagic we have all the products you need to help soothe and offer your dog relief from the itching that the allergies bring. Please get in touch if you need any advice on the right product to help your dog on 01624 829575…