Definition: Allergen

Definition: Allergen

Allergen
(Alérgeno)

An allergen is a substance that's capable of producing an allergic reaction. In some people with asthma, allergens that are breathed in can trigger symptoms such as coughing, wheezing, and shortness of breath. Allergens that commonly cause asthma symptoms include animal dander, dust mites, mold, and pollen.