It sounds as if your dog may have atopy, a common condition also known as allergic inhalant dermatitis. This means she could be allergic to substances such as indoor dust mites, feathers and moulds, as well as pollens from trees, weeds and grasses. At first, the scratching only occurs at some times of the year but, over time, many allergic animals begin scratching almost continually. The good news is that there are treatments available once you’ve identified the problem.
What to watch for
Atopy is fairly common in dogs but also occurs in cats. Many dog breeds are prone to this condition (terriers for example, as well as English and Irish setters). Dogs will scratch themselves frequently with their hind feet and lick or chew their paws or along their legs. Some also try to relieve the itch by rubbing their faces and ears along the carpet. Allergic cats will often groom excessively, sometimes to the point of licking themselves bald and some have respiratory problems such as coughing or wheezing.
All this scratching, licking and rubbing is hard on your pet’s skin, which becomes red and irritated. Hair loss is common, and dogs often develop seborrhea (flaky greasy skin) and secondary bacterial and yeast infections. It’s no wonder atopic dogs are often pretty smelly.
Finding the cause
To determine the reason for your pet’s scratching, your vet will ask questions about her diet and environment. Let your vet know if you are using any grooming products, whether other pets or people in the house are itchy and whether there’s a seasonal pattern to the symptoms. With atopy, itching begins insidiously and gradually worsens, but this can also be true of food allergies and bacterial or yeast skin infections. On the other hand, itching that begins suddenly and rapidly gets worse probably means fleas, mites or a drug reaction. If your vet identifies atopy as the likely cause, skin allergy testing may be done to confirm the diagnosis and identify exactly what your pet is allergic to.
Stop the itch
Your vet will work with you to develop a plan to manage your pet’s allergies; treatment may include gentle, moisturizing anti-itching shampoos, fatty acid supplements, antihistamines, allergy shots, short-acting corticosteroids for flare-ups and antibiotics for infections.
Reducing your pet’s exposure to a particular allergen is an important preventative measure, but remember that atopic animals are usually allergic to more than one thing and commonly develop new allergies over time. You may be able to avoid some allergens altogether (if your dog is sensitive to feathers or tobacco smoke for example) and reduce contact with others (by keeping your pet out of carpeted areas to reduce dust-mite exposure or starting flea preventatives early in the summer).
If it’s impossible to protect your pet from allergens and her symptoms persist or are difficult to control, your vet may recommend hyposensitization (also called immunotherapy). As with human allergy shots, your vet will inject your pet with low doses of the substances to which she is allergic. These treatments will be repeated regularly at first; boosters will then be administered as needed.
Allergies are a lifelong condition that you can best manage through a combination of strategies. With care and treatment, most allergic animals can live out their lives comfortably and happily.
Dr. Alice Crook co-ordinates the Sir James Dunn Animal Welfare Centre at the Atlantic Veterinary College at the University of Prince Edward Island. She also chairs the Animal Welfare Committee of the Canadian Veterinary Medical Association.