April 05, 2024 | Dog

What is atopy in dogs?

Atopy, or Canine Atopic Dermatitis as it is otherwise known, is an allergic skin condition in dogs, leading to redness and damaged skin along with fur loss. It is thought to affect 10-15% of the dog population in the UK, and is caused by a reaction to certain allergens in the environment of that dog, and is a lifelong condition.

Certain breeds of dogs appear to be more pre-disposed to atopy than others and examples include  Labrador and Golden retrievers, English Springer spaniels, Hungarian Vizslas, Basset hounds, Rhodesian Ridgebacks, Boxers, Chinese Shar Pei, West Highland white terriers, Bull terriers, French Bulldogs, Bichon Frisé and Tibetan terriers.

As certain families of dogs are also predisposed to this condition, there is thought to be a genetic component to it too.

Atopy in dogs

What causes atopic dermatitis?

The outer layer of a dog’s skin is called the epidermis and in atopic dogs, this layer is defective meaning that when allergens come into contact with the skin, the dog’s immune response goes into overdrive, creating an inflammatory response, resulting in itchiness. Typical allergens include specific types of pollens and moulds, dust mites and many other substances.

What are the signs of atopy in dogs?

The most common sign is excessive itchiness, which may be worse at certain times of year (seasonal) depending on the prevalence of the allergens to which that dog reacts. Dogs react by scratching their elbows, licking and chewing their paws, rubbing their faces, or scooting on their bottom. The areas where the rubbing or scratching takes place may appear red and the hair or fur in those places often takes on a brownish colour due to staining by the dog’s saliva.

As the condition progresses, areas of the skin become thickened and darker (lichenified), and secondary infections appear as rashes on the skin - often seen on the dog’s tummy, behind their front legs and at the base of the tail.

What conditions are associated with atopy?

Specific conditions that are associated with atopy include:

  • Ear and skin conditions

  • “Hot spots” - localised areas of dermatitis

  • Allergic conjunctivitis (excessive tear production and redness of the conjunctiva of the eyes)

  • Allergic rhinitis (excessive sneezing)

  • Flea and food allergy dermatitis

How is atopy diagnosed?

There is no specific test for atopy, and so a diagnosis is often made on the basis that one or more of the following boxes is ticked:

  • Classic signs of excessive and prolonged itchiness

  • Exclusions of other conditions that may cause similar clinical signs

  • Bacterial or fungal skin infections

  • Fleas or other parasites such as skin mites

  • Ultimately, successful responses to treatments for atopy

What is the treatment for atopy?

Often, a combination of therapies is required to control the condition, and therapy criteria may change over the course of the year, as certain allergens such as specific pollens, are more plentiful at certain times of the year - in other words, there may be seasonal variation in a dog’s immune response.

It is important to control any trigger points as much as possible - such as avoiding certain foods if there is a dietary allergic reaction, and keeping on top of flea and other skin parasite treatments if there is a known sensitivity to these factors; any secondary bacterial or fungal treatments may also need treating with appropriate antibiotics or antifungals.

Some topical therapies can help by removing the allergens and moisturising the skin as well as treating secondary skin infections and include shampoos, rinses and medicated wipes. Some products also contain antihistamines and corticosteroids to help reduce inflammation.

If the allergens are dietary related, specific veterinary hypoallergenic diets may help (finding one that suits your dog may be a bit of trial and error) and it is usually crucial to feed only this food to keep things under control.

Allergen-specific immunotherapy

Testing can be performed to try and identify which allergens are the causal ones in your dog’s atopic response. This is usually done by taking a sample of your dog’s blood and then sending it off to an external laboratory for testing to look for IgE antibodies against specific allergens, or by injecting small amounts of allergens into your dog’s skin to see how the skin reacts. Based on these tests, immunotherapy specific to your dog can be designed and administered to your dog periodically, usually through a subcutaneous injection or under the tongue.

Oral Medications

Several different oral medicines are available which may help to control the clinical signs of atopy. These include:

  • Corticosteroids - can be useful for acute flare-ups, but are best used for short-term use only due to long-term side effects

  • Antihistamines - useful for treating mild itchiness but must be used early in the reaction process to be effective

  • Cyclosporine - this reduces the immune response in the body of the affected dog, thus reducing the clinical signs

  • Oclacitinib- a newer medication which is very effective in reducing itchiness but without the harmful side effects of steroids

Injectable Medications

Lokivetmab is a monoclonal antibody which targets and neutralises one of the main proteins in your dog’s body (interleukin 31) which causes itchiness, thus reducing the itchiness.

Comment from Dr Rachel Louise Keane:

Dr Rachel Louise Keane BVSc BSc MRCVS of PocketVet believes that the treatment and management of atopy is important for your dog’s health and happiness:

“Atopy is a lifelong allergic condition and for this reason, it can massively impact the health and well-being of your dog. There are many different treatment options out there but often a combination of therapies, along with environmental management (which may be parasite control or dietary) may be needed, regardless, prompt diagnosis and identification of the causal agent is crucial to achieving a satisfactory outcome from treatment and for keeping your dog happy, comfortable and content.”

Medically reviewed by:


What is Canine Atopic Dermatitis? - The University of Nottingham

Atopic dermatitis in the dog – is treating the itch enough? - Veterinary Practice (veterinary-practice.com)

Canine Atopic Dermatitis - Integumentary System - MSD Veterinary Manual (msdvetmanual.com)

Skin allergies in dogs - PDSA

Atopic dermatitis (atopy) | Cornell University College of Veterinary Medicine

Canine atopic dermatitis – what have we learned? - Nuttall - 2013 - Veterinary Record - Wiley Online Library