An allergy is a state of over-reactivity or hypersensitivity of the immune system to a particular substance called an allergen. The allergen protein may be of insect, plant or animal origin. Exposure to the allergen, usually on multiple occasions, sensitizes the immune system, and a subsequent exposure to the same or related allergen causes an over-reaction.
What are the symptoms of allergies in dogs?
In the dog, the most common symptom associated with allergies is itching of the skin, either localized (in one area) or generalized (all over the body). This can manifest as ear infections, "hotspots", redness on the abdomen, or chewing at the feet or other areas.
How common are allergies in dogs?
Unfortunately, allergies are quite common in dogs of all breeds and backgrounds.
What are the common allergy-causing substances (allergens)?
A very large number of substances can act as allergens. Examples of common allergens are pollens, mold spores, dust mites, shed skin cells (similar to "pet allergies" in humans), insect proteins such as flea saliva, and some medications. Food allergies are also very common.