Introduction

Atopy is an extremely common, genetically-influenced disease that causes dogs to become hypersensitive to things that normally would not cause them to have an allergic reaction. Also known as allergic inhalant dermatitis, atopic dermatitis, “skin allergies” or atopic eczema, canine atopy is characterized by chronic itchiness (prurutis), which often is seasonal and typically affects the feet, face and underbelly. It commonly is associated with self-inflicted trauma from scratching or biting at the itchy areas. Secondary skin afflictions are also seen. Atopy can be so severe that it interferes dramatically with a dog’s quality of life.

Symptoms of Atopy in Dogs

Owners of affected dogs may notice one or more of the following symptoms, which are the hallmarks of canine atopic dermatitis:

• Itching, scratching and rubbing (intense, chronic, often seasonal; especially feet, face and underbelly)
• Licking (intense, chronic, often seasonal; especially feet, face and underbelly)
• Biting, chewing (intense, chronic, often seasonal; especially feet, face and underbelly)
• Sneezing
• Runny nose (allergic rhinitis)
• Watery eyes (ocular discharge; excessive tearing)
• Skin and coat discoloration (brownish-red) from salivary staining
• Bumps, lumps, pustules on affected skin areas
• Sores (raw, weeping “hot spots”) from self-trauma
• Deep scratches in the skin (excoriations)
• Scabs; crusting of the skin surface
• Greasy or flaky skin
• Hair loss (alopecia)
• Skin infection (from self-trauma and secondary bacterial infection)
• Red, swollen, inflamed, irritated ears and ear flaps
• Ear canal infections (otitis externa; recurrent; bacterial or yeast)
• Dark, waxy ear exudates (profuse; often smelly)
• Unpleasant, “yeasty” ear odor
• Skin thickening and darkening in affected areas

In addition to the feet, face and abdomen, frequently affected areas include the base of the tail, the groin area, around the eyes, around and inside the ears, under the front legs (in the “armpits,” called the axial area), between the toes (interdigital space), on top of the feet and on the muzzle. Most dogs first show signs of atopy when weed pollens become prevalent, in late summer and early fall. Additional tree and grass pollens and other environmental allergens become especially common in the spring. Of course, allergens inside the house, such as dust, wool, plant fibers, mold, feathers, mites, fleas, animal dander and the like, often contribute to year-round allergies in companion dogs. Unfortunately, most dogs with seasonal atopy eventually progress to having non-seasonal, year-round disease, and most symptoms of atopic dermatitis worsen with time. Atopy cannot be cured, but usually it can be controlled. If your dog suffers from these clinical signs, consider scheduling an appointment with your veterinarian as soon as you can.

Dogs at Increased Risk

There is no clear sex predisposition for atopic dermatitis, although it is slightly more common in female dogs. While the age of onset can vary widely, atopy is most frequently first seen in young dogs between 1 and 3 years of age. Certain breeds are more susceptible to the disorder, including the Chinese Shar-pei, Cairn Terrier, West Highland White Terrier, Boston Terrier, Boxer, Scottish Terrier, Sealyham Terrier, Lhasa-Apso, Shih-Tzu, Wire-Haired Fox Terrier, English Bulldog, Pug, Poodle, Dalmatian, Irish Setter, English Setter, Golden Retriever, Labrador Retriever and Miniature Schnauzer. However, any breed of dog, including mixed breed dogs, can suffer from this condition.