Allergic rhinitis, an allergy that causes symptoms involving the nose, is a condition that affects an estimated 40 to 60 million people in the United States.
Hay fever is a common name for allergic rhinitis, but hay is only one of many allergens that can cause the condition, and fever is not a symptom associated with allergic rhinitis.
Like other allergies, allergic rhinitis develops when the body's immune system becomes sensitized and overreacts to something in the environment that typically causes no problem in most people.
There are two forms of allergic rhinitis: seasonal and perennial. As the name suggests, seasonal allergic rhinitis occurs during a particular season, usually spring, summer, or early fall. Perennial allergic rhinitis causes symptoms year-round.