histamine

noun his·ta·mine \ ˈhi-stə-ˌmēn , -mən \

|Updated on: 21 Jun 2018

Definition of histamine

: a compound C₅H₉N₃ especially of mammalian tissues that causes dilation of capillaries, contraction of smooth muscle, and stimulation of gastric acid secretion, that is released during allergic reactions, and that is formed by decarboxylation of histidine

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Recent Examples of histamine from the Web

On the second and subsequent occasions when peanut protein comes along, the mast cells recognize it and start producing histamine and other immune compounds.

— amber dance, Washington Post, "Peanut allergy is one of the most severe food allergies. New therapies might help.," 12 May 2018
Earlier experiments in which people breathed in histamine found that just 24.5μg could affect breathing.

— beth mole, Ars Technica, "More nightmare fuel: Bedbugs create cesspool of poop and histamine in your bed," 14 Feb. 2018
If emollient treatment fails, other options include topical and oral steroids, anti-histamines or oral itch suppressors, or even antibiotics.

— Philly.com, "Bath additives not needed to treat eczema," 8 May 2018
Green or white tea: These drinks contain compounds called catechins, which block the creation of histamines (the chemicals that cause allergy symptoms).

— kim tranell, Redbook, "Eat These Foods to Fight Allergies," 25 Feb. 2013
Our immune system mistakes pollen as a foreign threat and releases antibodies that attack the allergens, which then releases histamines, causing the familiar runny nose, itchy eyes and throat among other possible symptoms.

— NBC News, "How to prep your home for allergy season," 4 Apr. 2018
With a food allergy, your immune system makes too much of an antibody that then fights the threatening food allergens by releasing histamines and other chemicals.

— gary kleiner, m.d., ph.d., miamiherald, "Children’s food allergies can be minor — or life threatening | Miami Herald," 27 Mar. 2018
But that limit is based on ingesting histamine, not breathing it.

— beth mole, Ars Technica, "More nightmare fuel: Bedbugs create cesspool of poop and histamine in your bed," 14 Feb. 2018
The chemical histamine, which regulates much of the inflammatory response, is also a monoamine, so perhaps there’s a link there too?

— dean burnett, The Cut, "Thinking Beyond the ‘Chemical Imbalance’ Theory of Depression," 11 Jan. 2018

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

Origin and Etymology of histamine

International Scientific Vocabulary hist- + amine

NEW! Time Traveler

First Known Use: circa 1913

in the meaning defined above

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HISTAMINE Defined for English Language Learners

histamine

noun

Definition of histamine for English Language Learners

medical : a chemical substance in the body that causes the symptoms that people experience when they are allergic to something

Medical Dictionary

histamine

noun his·ta·mine \ ˈhis-tə-ˌmēn , -mən \

medical Definition of histamine

: a compound C₅H₉N₃ especially of mammalian tissues that causes dilatation of capillaries, contraction of smooth muscle, and stimulation of gastric acid secretion, that is released during allergic reactions, and that is formed by decarboxylation of histidine

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