Canine atopy is similar to hay fever in humans, but instead of causing runny nose / eyes and sneezing, the vast majority of veterinary atopy cases result in itchy skin. Some animals do suffer from asthma or related respiratory signs, but they are in the minority. Atopy is thought to be heredity, so breeding atopic animals is discouraged.
Itchy skin often leads to scratching, licking and biting. This causes trauma to the skin, leading to breakage and loss of hair and skin infections. The infection (dermatitis) often causes more itching, sometimes pain, and invite more scratching, licking and biting, repeating the cycle.
In contrast to a food allergy that will develop and be present as long as the food is eaten (year round), atopic animals often start out with seasonal "peaks" of itchy skin but over time, the peaks often last longer and longer as the animal is repeatedly exposed to the offending allergen(s). Atopy and the resulting dermatitis signs are usually seen early in life; between 1-3 years of age, but may develop later. Some animals may then experience itchy skin year round as their allergic sensitivity increases.
An itchy pet is uncomfortable --- all of that scratching, licking and biting invites a host of other problems, including chronic ear infections, hot spots and sebborrhea. Brown to red "saliva stains" may also be seen on light-coated animals. A visit to the vet is the first step in finding out the cause of the itchy skin and providing treatment.
There are skin and blood tests available to help determine what a pet may be allergic to. Skin tests are considered to be more accurate. Skin testing is usually more expensive and requires more "participation" to complete the test. In addition to allergy testing, the veterinarian will want to rule out other causes of itchy skin, such as: mites, fleas, food sensitivity, fungal or bacterial infection, or reaction to medication.
Atopy can be a frustrating problem to treat, but keeping a diary of how treatment is progressing (or not) and good communication with your veterinarian will help.
Atopy treatment is three-fold:
- reduce exposure to the allergen(s) if possible
- testing and "allergy shots" to reduce sensitization to the allergen(s) -- also known as hyposensitization therapy
- control the itching and self trauma with medications such as: cortisone, antibiotics (if needed), fatty acid dietary supplements, antihistamines and soothing anti-itch shampoos and conditioners
Canine Atopy from the Atlantic Veterinary College, University of Prince Edward Island, and the Canadian Veterinary Medical Association.
Photo credit: Scratching dog © blmurch on Flickr