Allergies in Dogs
The most common symptom of allergies in dogs is itching. If your dog often licks, chews, or scratches at his skin, he very likely has allergies. There are many tools available to make our itchy dogs comfortable again. But there are many causes of itchy skin, and it takes time and a proper diagnosis to find the right solution. Common allergens in dogs Allergens in dogs can be divided into three groups: airborne and contact allergens, flea allergy dermatitis, and food allergens. Airborne and contact allergens include plant pollen (from trees, grasses, and weeds), mold spores, dust and dust mites,…
The most common symptom of allergies in dogs is itching. If your dog often licks, chews, or scratches at his skin, he very likely has allergies. There are many tools available to make our itchy dogs comfortable again. But there are many causes of itchy skin, and it takes time and a proper diagnosis to find the right solution. Common allergens in dogs Allergens in dogs can be divided into three groups: airborne and contact allergens, flea allergy dermatitis, and food allergens. Airborne and contact allergens include plant pollen (from trees, grasses, and weeds), mold spores, dust and dust mites, and skin dander. These allergens cause itchiness in allergic dogs when the allergens are breathed in, make contact with the dogs’ skin, and/or are licked off the dog’s feet and coat. These allergies often have a seasonal component (and are referred to as “seasonal allergies”). When a seasonal link is not observed (such as with an allergy to dust and/or dust mites), this may be called “environmental allergies.”Flea allergy dermatitis (FAD) – where an allergic response to the saliva of fleas, injected in the dog’s skin when the flea bites, causes inflammed, itchy skin – is a very common disorder in dogs.Food allergies are not common in dogs. For those dogs who do have a food allergy, the most common food allergens are chicken, beef, dairy, and eggs. Grains – including corn and wheat – are the least common food allergens in dogs. Symptoms of allergies Dogs with allergies can be itchy anywhere on their bodies. However, most dogs with allergies caused by pollen, mold spores, indoor allergens, and food will be itchy primarily on the underside of their chest and belly (including the armpits and groin), around the butt under the tail, paws, ears, and around the eyes and lips. Dogs with flea allergy dermatitis are primarily itchy on their back in front of their tail, and on their thighs, underside of the belly, neck, and ears. An allergic dog may chew, lick, and scratch at his skin, damaging the skin’s protective barrier. The protective barrier is composed of oils and the bacterial skin flora. Damaging this barrier is like filling in the moat around a castle; it allows opportunistic bacteria and yeast to gain access to the deeper layers of skin. A dog who is itchy and has red, irritated, or damaged skin and hair loss in those areas is said to have atopic dermatitis. This is an inflammatory condition characterized by an increased production of IgE antibodies in response to an allergen. Ectoparasites such as mites can also cause itchy skin but are not atopic dermatitis. llergy tests and allergy diagnosis In an intradermal skin test, a veterinary dermatologist injects a small amount of the most common allergens that are suspected to cause the dog’s allergies, one bleb of allergen to each spot marked by a pen in a grid on the dog’s skin. After a few minutes, each spot where a substance was injected is examined for the presence of a wheal (raised red swelling of the skin). The appearance of a wheal indicates that the dog is allergic to the substance injected in that spot. Photo by Firn, Getty Images. Allergies are a diagnosis of exclusion. There are a lot of conditions that look like atopic dermatitis (see “Seriously Itchy Paws,” WDJ November 2022), so these need to be diagnostically ruled out before concluding that allergies are causing your dog’s itching and irritated skin. Observation of the timing and frequency of your dog’s itching can help diagnose allergies and help pinpoint the allergen that your dog is sensitive to. If your dog is itchy at the same time every year he has a seasonal allergy. Tree, grass, or weed pollen that is prevalent at a certain time of year will trigger your dog’s itching. His sympt…
