MedlinePlus Medical Encyclopedia: Allergic reactions

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Allergic reactions

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 anaphylactic shock.

Update Date: 5/18/2006

Updated by: Donald Accetta, MD, MPH., President, Allergy & Asthma Care, PC, Taunton, MA. Review provided by VeriMed Healthcare Network.

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