Allergies in Pets
Hay fever symptoms, and allergies in general, are extremely common in people. Pets get allergies too, though their symptoms are different. Pollens, molds, mildews and dust mites cause sneezing, congestion, coughing and eye irritation in humans. In dogs and cats, itchy skin is more common, especially the skin of the face, feet or legs, and ears. In pets and people, this form of allergy is called atopy. Dermatitis (skin inflammation) caused by atopy is called atopic dermatitis.
Atopy is reported to affect between 3 and 15% of the dog population. Up to 80% of dogs with atopy are also allergic to fleas and up to 30% are allergic to foods. Itchy cats, who will often groom themselves excessively and develop bald patches of skin on their legs, back or belly, have atopy 15-17% of the time, and food allergies 13-17% of the time. Many cats have both problems.
The tendency toward allergies is genetic, so atopy can run in families and be more common in certain breeds of dogs. The risk of a human infant developing atopy is 37% if one parent also has atopy and 62% if both parents do. If you are purchasing a puppy from a breeder, ask about the history of allergies in the parent dogs and their parents as well. If two or more parents or grandparents had skin or ear problems it may be best to choose a different litter.
Pollen allergy tends to be seasonal. Ragweed blooms in late summer and fall, and is a common allergen for both people and pets. Itching from ragweed will usually be most severe in August and September. Tree pollen is most prevalent in the spring, and summer brings grass and weed allergies. If a pet is itchy or gets ear infections throughout the year, indoor allergens like molds and dust mites may be the problem. These environmental allergies – caused by tiny spores we and our pets inhale and get on our skin – usually start to appear when a dog or cat is 2-5 years old. It takes a couple of seasons’ worth of exposure for the immune system to start to overreact to things. Once it starts, atopy tends to slowly worsen year by year.
Ear infection, or otitis, is common in pets with allergies. Recurrent otitis, especially yeast otitis, usually means the dog has an underlying allergy. 90% of food-allergic dogs have otitis, and 20% have otitis as their only symptom. 50-80% of atopic dogs have otitis.
Secondary Staph infections: Many allergic dogs develop secondary skin infections