ana·phy·lax·is | \ -ˈlak-səs \
plural anaphylaxes\-ˌsēz \

Definition of anaphylaxis 

1 : hypersensitivity (as to foreign proteins or drugs) resulting from sensitization following prior contact with the causative agent

Examples of anaphylaxis in a Sentence

Recent Examples on the Web

This can manifest as hives, itching, and watery eyes or anaphylaxis, a severe reaction that can include critical drops in blood pressure, difficulty breathing and possibly even swelling of the throat. Ronald S. Litman,, "Should I worry about my child being allergic to anesthesia?," 9 July 2018 Symjepi contains the same active ingredient, epinephrine, as EpiPen, which is used to treat anaphylaxis caused by insect bites and foods, among other allergic reactions. Peter Loftus, WSJ, "Novartis Injects Itself Into Planned Rollout of EpiPen Competitor," 2 July 2018 In more severe cases, anaphylaxis sets in, leading to trouble breathing, rapid heart rate, a dip in blood pressure and other dangerous symptoms. Amber Dance, Washington Post, "Peanut allergy is one of the most severe food allergies. New therapies might help.," 12 May 2018 This can cause mild annoyances like hives or itchy eyes, or life-threatening issues like anaphylaxis, where blood pressure plummets and airways start swelling shut. Umair Irfan, Vox, "It’s not your imagination. Allergy season gets worse every year.," 28 Apr. 2018 In 2016, the average ER visit for anaphylaxis cost $1,419, with an average patient out-of-pocket cost of $373. NBC News, "More kids are going to emergency rooms with severe allergies," 13 Mar. 2018 Peanuts and soy can induce asthma as part of anaphylaxis in those who are allergic; shellfish have been known to cause attacks as well. Brad Rickman, Condé Nast Traveler, "Traveling With Asthma," 17 Apr. 2018 The first line of treatment for anaphylaxis is a medicine called epinephrine. Gary Kleiner, M.d., Ph.d., miamiherald, "Children’s food allergies can be minor — or life threatening | Miami Herald," 27 Mar. 2018 While most people may develop itchy skin, tingling in their face, or hives some will experience more serious anaphylaxis, a life-threatening reaction that could cause death, according to LiveStrong. Mari A. Schaefer,, "Food allergies are no joke, say parents angry over new 'Peter Rabbit' movie," 12 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'anaphylaxis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of anaphylaxis

circa 1905, in the meaning defined at sense 1

History and Etymology for anaphylaxis

New Latin, from ana- + prophylaxis

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Last Updated

18 Aug 2018

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Time Traveler for anaphylaxis

The first known use of anaphylaxis was circa 1905

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More Definitions for anaphylaxis


ana·phy·lax·is | \ ˌan-ə-fə-ˈlak-səs \
plural anaphylaxes\-ˌsēz \

Medical Definition of anaphylaxis 

1 : hypersensitivity (as to foreign proteins or drugs) resulting from sensitization following prior contact with the causative agent

More from Merriam-Webster on anaphylaxis

Britannica English: Translation of anaphylaxis for Arabic Speakers Encyclopedia article about anaphylaxis

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