Anaphylaxis is a severe, whole-body allergic reaction to a chemical that has become an allergen. After being exposed to a substance such as bee sting venom, the person's immune system becomes sensitized to it. On a later exposure to that allergen, an allergic reaction may occur. This reaction happens quickly after the exposure, is severe, and involves the whole body. [[Tissues]] in different parts of the body release [[histamine]] and other substances. This causes the [[airways]] to tighten and leads to other symptoms. Anaphylaxis is life-threatening and can occur at any time. Risks include a history of any type of allergic reaction.
Anaphylaxis can have IgE-mediated, non IgE-mediated and nonimmunologic triggers. IgE mediated allergens include reactions to food, medications and animal dander. Non-IgE mediated reactions can be caused by IVIG, biologic agents and NSAIDs. Nonimmunologic triggers to anaphylaxis include radiocontrast media, opiates, and changes in temperature. <ref name="pmid28800865">{{cite journal| author=LoVerde D, Iweala OI, Eginli A, Krishnaswamy G| title=Anaphylaxis. | journal=Chest | year= 2018 | volume= 153 | issue= 2 | pages= 528-543 | pmid=28800865 | doi=10.1016/j.chest.2017.07.033 | pmc=6026262 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=28800865 }} </ref>
===Life Threatening Causes===
===Life Threatening Causes===
Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated. Anaphylaxis is itself a life threatening condition.
Anaphylaxis is itself a life-threatening condition caused by various allergens. <ref name="pmid28800865">{{cite journal| author=LoVerde D, Iweala OI, Eginli A, Krishnaswamy G| title=Anaphylaxis. | journal=Chest | year= 2018 | volume= 153 | issue= 2 | pages= 528-543 | pmid=28800865 | doi=10.1016/j.chest.2017.07.033 | pmc=6026262 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=28800865 }} </ref>
Anaphylaxis can have IgE-mediated, non IgE-mediated and nonimmunologic triggers. IgE mediated allergens include reactions to food, medications and animal dander. Non-IgE mediated reactions can be caused by IVIG, biologic agents and NSAIDs. Nonimmunologic triggers to anaphylaxis include radiocontrast media, opiates, and changes in temperature. [1]
Life Threatening Causes
Anaphylaxis is itself a life-threatening condition caused by various allergens. [1]
Causes
Common Causes
Anaphylaxis can occur in response to any allergen. Common causes include: [2][3][4]