Hay fever, or allergic rhinitis, is inflammation of the nose cause by nasal allergies. When the immune system identifies a harmless airborne substance as harmful, it produces antibodies that signal the immune system to release histamines in the bloodstream that result in hay fever symptoms. Common hay fever triggers include outdoor allergens such as pollens, indoor allergens such as pet dander, and irritants such as cigarette smoke. Treatment typically includes avoiding allergens and controlling symptoms with medications.
