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Allergen

Definition

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 IgE to defend against the allergen. This reaction leads to allergy symptoms.

Information

Common allergens include:

  • Animal proteins and animal dander
  • Dust
  • Drugs (such as antibiotics or medicines you put on your skin)
  • Foods (such as egg, peanut, milk, nuts, soy, fish, animal meat, and wheat)
  • Fungal spores
  • Insect and mite feces
  • Insect bites and stings (their venom)
  • Natural rubber latex
  • Pollen

Gallery

Positive reaction to allergen
Allergic reaction is a sensitivity to a specific substance, called an allergen, that is contacted through the skin, inhaled into the lungs, swallowed or injected. The body's reaction to an allergen can be mild, such as a localized rash, or life-threatening, such as anaphalactic shock.

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.

Last reviewed January 16, 2021 by Linda J. Vorvick, MD, Clinical Associate Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team..

Related specialties

Aftercare and more

Clinical Trials: Allergen

UF Health research scientists make medicine better every day. They discover new ways to help people by running clinical trials. When you join a clinical trial, you can get advanced medical care. Sometimes years before it's available everywhere. You can also help make medicine better for everyone else. If you'd like to learn more about clinical trials, visit our clinical trials page. Or click one of the links below:

News and Patient Stories: Allergen

More Allergen stories

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