Atopy is an itchy, inherited skin disease. It is caused by an allergy to substances that are contacted through the air, either by absorption via the respiratory tract or contact via the skin. It is the second most common allergic skin condition in dogs. Flea allergy dermatitis is more common. Antihistamines tend not to be helpful. Secondary bacterial infections are common. Immunotherapy is the ideal form of treatment and is recommended for dogs that cannot be managed safely and effectively with symptomatic therapy. This technique is effective in 60 to 80 percent of atopic dogs.
A newer therapy called Oclacitinib (Apoquel)
has been very effective in control of itching in dogs with allergies. This drug uniquely targets cytokines that are involved in the itch process. Onset of relief can be as early as 4 hours and controls the itch within 24 hours. Many veterinarians like this drug because it controls itching without the side effects of steroids.
For more information, please read the article Atopy