Deutsch: Allergen / Español: Alérgeno / Português: Alergênio / Français: Allergène / Italiano: Allergene /
An Allergen is a material that, as a result of coming into contact with appropriate tissues of an animal body, induces a state of allergy or hypersensitivity; generally associated with idiosyncratic hypersensitivities.
Other definition:
An Allergen is a substance capable of causing an allergic reaction because of an individual's sensitivity to that substance.
Other definition:
An Allergen is a substance that causes an allergic reaction in individuals sensitive to it.