Allergic rhinitis is a diagnosis associated with a group of symptoms affecting the nose. These symptoms occur when you breathe in something you are allergic to, such as dust, animal dander, or pollen. Symptoms can also occur when you eat a food that you are allergic to.
An allergen is something that triggers an allergy. When a person with allergic rhinitis breathes in an allergen such as pollen, mold, animal dander, or dust, the body releases chemicals that cause allergy symptoms.