Inhalant allergy or "atopy" is a common allergic skin disease in dogs. It is the canine equivalent of "hay fever" in humans, and its cause is allergy inhaled substances such as dust pollens, and molds. Some breeds appear to be more susceptible to atopy, as there seems to be a genetic predisposition in the development of the disease. They include the cocker spaniel, Dalmation, golden retriever, Labrador, poodle, Maltese, and all terriers.

Inhalant allergies usually show up when the dog is 1 to 3 years of age. At first, symptoms are seasonal (especially in the spring), but they tend to worsen and persist for longer periods as the dog grows older.

The first signs of allergic reaction are scratching, licking, biting, or rubbing the skin. This can lead to infection, which is characterized by red bumps and pimples. Dogs with atopy tend to experience itching the most on such areas as the face, ears, feet, and lower abdomen.

If the symptoms of atopy are seasonal and not year-round, a veterinarian may treat the dog with some type of steroid, antihistamine or special fatty acid supplement. This therapy relieves the dog's itching, often until the season for the allergen has passed. For long-term allergies, once the allergens have been identified, exposure to the allergens can be avoided, or the pet can be desensitized from them with allergy shots.

So if you notice your dog itching uncontrollably, the discomfort and possibility of secondary bacterial infection make it important to get professional help as soon as possible. It should be realized, however, that allergies are almost impossible to cure. They can only be controlled with the help of your veterinarian.

The writers are Dr. Steven B. Holzman, Dr. William R. Haagenson and Dr. Kathleen Tapley. They are associated with the Nassau-Suffolk Veterinary Hospital of Farmingdale.