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Allergen

An allergen is a substance that can cause an allergic reaction. In some people, the immune system recognizes allergens as foreign or dangerous. As a result, the immune system reacts by making a type of antibody called immunoglobulin E (IgE) to defend against the allergen. This reaction leads to allergy symptoms.

Images

Positive reaction to allergen

Information

Common allergens include:

Related Information

Allergic rhinitis - what to ask your doctor - adult
Allergic rhinitis - what to ask your doctor - child

References

Stewart GA, Robinson C. The structure and function of allergens. In: Burks AW, Holgate ST, O'Hehir RE, et al, eds. Middleton's Allergy: Principles and Practice. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 26.

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Review Date: 2/2/2023  

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