Allergic rhinitis is an allergic reaction of the lining of the nose.
Seasonal allergic rhinitis is also called hay fever. Allergic rhinitis occurs when the nose and usually also the ears, sinuses, and throat come into contact with allergy-causing substances. The allergy-causing substances are called allergens. The most common allergens are pollens, molds, dust, and animal dander. Some allergens are present only during certain seasons, for example, ragweed in the fall.