Allergic Skin Disease

All dogs will naturally scratch and lick themselves as part of their normal behaviour. However up to 1 in 3 dogs will be affected with allergic skin disease which can result in excessive licking, scratching and discomfort for your best friend. Allergic skin disease is seen in all breeds of dog but is particularly common in certain breeds including Westies, Staffies, Shar-Peis, Labradors, German Shepherds and English Setters. Dogs with allergic skin disease generally start being itchy at quite a young age (1-3 years of age) and usually the feet, face and ears, and tummy are the worst affected areas.

So what causes allergic skin disease?

FLEAS - Yes, fleas can be the cause and account for the majority of cases of allergic skin disease. All dogs can get fleas and all dogs find fleas annoying but only certain dogs are actually ALLERGIC to fleas (much the same as humans and bees). Whilst most dogs will tolerate a couple of fleas on them without too much stress, a dog that is allergic to fleas only needs to be bitten by one flea to create an intense itch. This is due to a severe reaction to the flea’s saliva and can only be treated with complete eradication of fleas from the dog’s environment- which means treating the dog’s environment (household and bedding) and well as any in-contact animals and obviously the dog itself. It’s also important to remember that you may not even see a flea on your pet and the vet might not even be able to find one during the physical examination, however an itchy dog must be thoroughly treated for fleas with high quality flea control before ruling out flea allergy dermatitis.

ATOPY - Inhaled or atopic dermatitis is the next most common allergy, and is worst in spring and summer when pollen burdens are highest. Like hay fever in humans, the allergen may be inhaled and avoidance is very difficult as air borne particles can travel in the breeze for many kilometres. House dust mites are found all year round, and in sensitive dogs they will cause year round itching. On occasions, dogs may be sensitive to mould spores that become airborne after rain or very high humidity. Dogs tend to show clinical signs at about 3 years of age, and these symptoms can vary from watery eyes, sneezing, frequent facial and bottom rubbing, generalised redness and itchiness and chronic ear infections. This type of allergy is best diagnosed with intradermal skin testing.

CONTACT ALLERGY -  is commonly seen in the warmer months of the year, and affected dogs show intense itching and inflamed skin under the tummy, in the armpits, on the chin and under the paws (these areas tend to have a thinner distribution of fur, and plant material is therefore more likely to come in direct contact with the skin). Certain plants such as wandering jew will often make dogs itchy, as do many other plants, lawn grasses and carpets.

FOOD – Whilst food is the least common allergen, certain dogs can have significant reactions to particular proteins in their diet-beef, lamb, dairy, chicken, wheat, eggs, corn and soy and being the common allergens. It’s important to note that to develop an allergy to a food dogs need previous exposure to this allergen and therefore it may be a diet that have been on for years. It’s also important to realise that even if they have been on the same brand of diet for a while, ingredients that the manufacturers use can change (ie a beef diet may also contain some chicken)- so when diagnosing and eliminating certain proteins from a dog’s life you must look at the full ingredient list on the bag.

Diagnosis of food allergy is challenging- a ‘new’ protein source (one the dog hasn’t been exposed to before ) needs to be fed for a period of up to 3 months to see if the symptoms improve, at which point a ‘challenge’ should be initiated, using the dogs previous diet, to observe whether symptoms persist.


In a nutshell, come and see us. We will tailor a diagnostic and treatment plan based on each dog’s clinical signs and frequency of attacks. Treatment options include antihistamines, corticosteroids, antibiotics, immunotherapy, vaccines and avoidance! It can take several visits to the vet to work out exactly what is going and the underlying culprit (or sadly in some cases, culprits) however lots can be done to improve these dog’s general well-being and quality of life.