Just like their owners, dogs and cats are frequently allergic to pollen, mold, dust mites, or other environmental triggers. A key difference, however, is that while people typically suffer sneezing and runny eyes, pets usually develop itchy skin. The underlying genetic tendency to develop allergies is called atopy, and the skin condition that results may be referred to as atopic dermatitis or allergic inhalant dermatitis.
Animals with allergies frequently have recurrent skin and ear infections, which can make them even itchier than they are normally. Often, symptoms are seasonal to begin with but become a year round problem as the disease progresses. Veterinarians will often suspect than an animal has atopic dermatitis based on its clinical signs and by ruling out other conditions that can cause similar symptoms (e.g., parasites or food allergies). Coming to a definitive diagnosis and identifying a pet's triggers requires either intradermal skin testing or specialized blood tests.
Treatment for skin allergies falls into two categories. The first is symptomatic therapy. Medicated baths and drugs that reduce itching and inflammation can make many animals feel much better, but symptoms will return once treatment is stopped and the pet is once again exposed to the allergen. Sometimes the side effects associated with the long-term use of some of these medications are unacceptable. The second way to treat allergies is called hyposensitization. A veterinarian, usually a veterinary dermatologist, will formulate a serum that contains the triggers to which a pet has had a positive reaction during allergy testing. Repeated injections of the serum (i.e., allergy shots) allow the immune system to become less sensitive to the allergens and in some but not all cases, can greatly reduce an animal's symptoms. Pet "parents" must be aware that, no matter what course of treatment they elect, allergies cannot be cured, only managed.
Written by: Jennifer Coates, DVM
Last reviewed: October 2, 2008