Like human allergies, it is brought on by seasonal pollens and other airborne allergens. Affected dogs persistently scratch, lick, bite and may present with ear problems. The constant scratching produces sores, hair loss and secondary infections called hotspots.

Cats suffering from allergic dermatitis constantly scratch and groom and may develop respiratory symptoms.

Allergic dermatitis is caused by sensitivity to environmental allergens including dust mites, tree, grass and weed pollens.

The animal’s immune system over-reacts to the allergen and excess histamine and other inflammatory agents cause skin inflammation and itching. Allergens to pollens are mostly seasonal, but can get worse each year with additional allergen exposure.

Diagnosing atopic dermatitis excludes other possible allergic skin conditions like flea allergy dermatitis and food and contact allergies (shampoos, soaps, detergents, plants, grass etc.). Blood tests can confirm atopic dermatitis and indicate what allergies are causing the problem.

A more sensitive test can be undertaken by veterinary dermatologists where small amounts of allergen are injected into the skin and any allergic reactions noted.

Treating atopic dermatitis can be frustrating as avoiding the offending allergen is often impossible. Fortunately there are treatments to relieve the constant suffering that itchy pets endure including:

- Cortisone: a potent anti-inflammatory that quickly lessens redness, swelling and itchiness.

- Antihistamines: have some anti-inflammatory effect with less side effects than cortisone.

- Food supplements: omega-3 fatty acids help prevent the dry flaky skin seen in atopic patients.

- Antibiotics and antifungal drugs: treat secondary bacterial and fungal infections.

- Topical treatments: including medicated or soothing shampoos and conditioners containing oatmeal and aloe vera.

- Hypo-sensitisation vaccines: can be prepared by specialist dermatologists.

Medication (atopica) that targets immune cells involved in allergic reactions has proven very effective for long-term control. Apoquel is another recent medication developed for atopic dermatitis in dogs with fewer side effects than steroids.

Long-term management of atopic dermatitis entails following your veterinarian’s advice and always giving medication on time. It can be tempting to stop treatment when symptoms improve, but without treatment symptoms will certainly reoccur.

Wash your pet’s bedding regularly, preferably with a hypo-allergenic detergent, vacuum frequently with a high efficiency particle air (HEPA) filter cleaner, use air dehydration and purification systems and use insecticides routinely against dust mites and fleas, maintaining rigorous flea control at all times.