Allergies are just as common in pets as in people. They often present as licking of the rear or feet, scratching at the sides or ears, shaking of the head, inflammation of the eyes, or inflammation of the skin. There are many causes of allergies in dogs. The most common causes are inhaled allergens (also called atopy or atopic dermatitis), food or allergy to flea saliva. Left untreated, allergies often cause secondary infections of the skin ears and eyes. A variety of medications can be used to control allergies, many of which were first developed for human allergies. Antihistamines (Benadryl), and corticosteroids (prednisone) may be used to control allergies by reducing itching and inflammation. Allergy testing, either on the skin or the blood, may help diagnose what your pet is allergic to. Food trials can help diagnose a food allergy. Regardless of the cause, allergies can be a frustrating problem that seriously affects the quality of life in your pet.