Seasonal allergies, or atopy, are one of the most common skin disorders in dogs. Atopy is an inherited allergic reaction to allergens (pollen, grass, mold, etc.) that are absorbed across the skin. Affected dogs also have certain areas of the body where the skin is defective and doesn’t form a good barrier. These two combined can cause affected dogs to be intensely itchy and uncomfortable as well as making their skin more susceptible to bacterial and yeast infections.
Before we even begin to try to control atopy, it is crucial that any other contributors to the itching are treated first. It means effective flea and tick prevention and treating any other skin issues (mite, bacteria and yeast infections). Sometimes low thyroid hormone level (dogs) can make the skin barriers weak and lead to infection and itching. Once these issues are under control, treatment options for the atopy can be explored.
It is important to understand that atopy is a chronic disease, and our goal is to improve your pet’s quality of life and to decrease the itching. It is a disease that is controlled, rather than “cured.” Your veterinarian will tailor a treatment plan to your dog, taking into account your pet’s tolerance to the treatment and also your ability to administer it. Your dog will likely have flare-ups from time to time, making it necessary to alter the treatment plan. Because atopy is so common and severe, there are several treatment options: supportive care, medications: corticosteroids, cyclosporine (Atopica), oclacitinib (Apoquel), Cytopoint (CADI-immunomodulatory), and immunotherapy. Many of these treatments work better in combination to provide relief.
Supportive care
It is always a good place to start if the dog is mildly itchy. Supportive care consists of essential fatty acids, bathing, restoring the skin barrier, control of secondary infections, topical anti-inflammatory products, and antihistamines. The advantage is it doesn’t cost as much, is very safe, and you see relatively quick benefits. It doesn’t require monitoring blood work or more expensive medications. The downside is that it is not as effective as drugs and is labour-intensive.
Bathing is critical. It will physically remove the allergens, reduce the bacteria and yeast populations, repair the skin barrier defects, and the tepid/cool water will help cool hot, inflamed skin. You will want to use a veterinary prescription shampoo that contains moisturizers or barrier repair ingredients, once or twice weekly. Despite the widespread belief that frequent baths will dry out the skin, most dermatologists agree that you cannot over bathe an allergic dog provided you use a conditioner /moisturizer after bathing. It is very important: you’ll also need to follow the bath with a veterinary skin barrier repair product and moisturizer. It will help restore the skin barrier, reduce skin water loss, and decrease the absorption of the allergens across the skin. Remember if your pet has atopy, you will want to choose a flea/tick preventative that is not susceptible to being washed away from repeated bathing.
Antihistamines may help some dogs, although they will likely not help if your pet is having an acute or intense flare. The main value of these drugs is to try to decrease the amount of other, more expensive, drugs for the itching. If you know your pet gets itchy at a very certain time each year, these are most effective if given before a flare occurs, and given on a continuous daily basis.
Essential fatty acids (omega-3) are recommended by most dermatologists, as there is some evidence that they help with the skin barrier. As with antihistamines, EFAs are not adequate as a single therapy, except in mildly affected patients.
Reduce allergens on the coat by wiping down your pet’s coat at least once daily to try to remove the allergens. Some people wipe down the coats and feet after walks or playing outside. Keep the hair coat short to reduce the “dust mop” effect of a longer coat. Use t-shirts and boots or socks to provide a physical barrier to the allergens.
Medications
Often, when symptomatic therapy is not enough, we must resort to medications. As with any drug, it’s important to look at the risk vs. benefit to the pet. Your veterinarian, who knows your pet, can tailor the treatment.
Corticosteroids (prednisone/prednisolone/dexamethasone) are inexpensive and work very well to reduce itching. If finances are limited or if the dog has seasonal symptoms without infection, they can help quickly. They are the only drug that works well to decrease swelling in ear canals. However, they have numerous short term (excessive drinking, urinating, eating, panting, etc.), and long term (liver and endocrine as well as having a negative effect on the skin barrier) effects.
Cyclosporine (Atopica) can help many allergic pets but can be one of the more expensive therapies to maintain except in very small patients. It also can often cause GI disturbance and uncommonly some gingival overgrowth.
Oclacitinib (Apoquel) is a relatively new drug works very well to help to itch with few side effects quickly. It is more expensive, especially for larger dogs that need a higher dose. For some dogs, after the initial twice-daily dosing regimen is decreased to once a day, itching can resume near the 24-hour mark. As with other options for treating atopy, it doesn’t work to control all itching in all patients, and additional therapies might be needed.
Cytopoint (CADI) is a dog-specific antibody used to decrease inflammatory responses in dogs. Because this is a normal antibody that the dog already has, it is safe with other drugs and can be repeated every 1-2 months, if needed.
Immunotherapy (Allergy Specific Immunotherapy or ASIT) = “Allergy shots.”
For many patients with atopy, ASIT can be one of the easier, safer, and more cost-effective therapies. It has a long-term track record of safety and efficacy. It is the only effective therapy that is not a drug and the only one without negative effects on the immune system. It involves blood or skin testing to determine which allergens are affecting your pet. Once results are obtained, the dermatologist can formulate a plan for treating your pet with “allergy shots” much the same as in human medicine. Another recent breakthrough is the development of allergy serum that can be given orally, under the dog’s tongue, where it is absorbed. This is not as effective as the injections; however, for some dogs, it works well.
Atopy is a frustrating disease for clients, veterinarians, and above all for the dog. However, with close communication with your veterinarian and medical therapy tailored to your dog, it can be managed and greatly improve your dog’s quality of life.
If you have any questions, please give us a call at 902.826.1933.
Written by: Dr. Alex Hare, DVM
