Dogs can develop allergies, in the same ways as people, to various foods (such as corn, grain, fish, poultry, and beef) as well as pollen, dander, and fleas. Pollen, invisible to humans but floats through the air, causes a grass allergy. Your dog may experience an allergic reaction if these tiny spores are absorbed through their skin and nasal passages. Furthermore, pollen can be absorbed by your dog's fur from surfaces other than grass, like the earth, which contains grass pollen. You may carry pollen from your dog's coat, shoes, and body during the spring and early summer, even if you keep your dog inside.

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