An allergy is an overactive response by your body to substances that, in most people, would not normally cause a problem. These substances are called allergens. The symptoms of allergies are similar to those of a cold.
Allergies affect the mucous membranes of the eyes, nose and upper air passages.
They can cause itchy, watery, red eyes, sneezing, runny nose, congestion and itchy throat and mouth. There are several different kinds of allergies, but the one most of us are familiar with is called seasonal allergic rhinitis, also known as hay fever. This allergic condition occurs during the spring and fall when you breathe in certain allergens. Typical allergens that cause seasonal allergic rhinitis are grass and tree pollens, molds and ragweed pollen. Many people suffer from allergies year-round.