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[his-tuh-meen, -min] /ˈhɪs təˌmin, -mɪn/
Biochemistry, Physiology. a heterocyclic amine, C 5 H 9 N 3 , released by mast cells when tissue is injured or in allergic and inflammatory reactions, causing dilation of small blood vessels and smooth muscle contraction.
Pharmacology. a commercial form of this compound, obtained from histidine and used chiefly in the diagnosis of gastric and circulatory functions.
Also, histamin
[his-tuh-min] /ˈhɪs tə mɪn/ (Show IPA)
Compare antihistamine.
Origin of histamine
1910-15; hist(idine) + -amine
Related forms
[his-tuh-min-ik] /ˌhɪs təˈmɪn ɪk/ (Show IPA),
adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for histamine
  • Those travel to cells that release histamine and other chemicals and cause an allergic reaction.
  • The researchers detected a spike in the calcium levels inside the cells, which is the first step in histamine secretion.
  • During the reaction, histamine and other chemicals are released into the bloodstream.
  • histamine is one of the chemicals released when antibodies overreact to allergens.
  • Tissues in different parts of the body release histamine and other substances.
  • When you have an allergic reaction to a substance, your body releases histamine and other chemicals into your bloodstream.
  • In a true food allergy, the immune system produces antibodies and histamine in response to the specific food.
  • It could be that it's a deficiency in histamine that may be part of the problem.
  • The damaged tissue releases chemicals including histamine, bradykinin, and serotonin.
  • Antihistamines block the histamine receptor on mast cells, which are the main culprits in allergic reactions.
British Dictionary definitions for histamine


/ˈhɪstəˌmiːn; -mɪn/
an amine formed from histidine and released by the body tissues in allergic reactions, causing irritation. It also stimulates gastric secretions, dilates blood vessels, and contracts smooth muscle. Formula: C5H9N3 See also antihistamine
Derived Forms
histaminic (ˌhɪstəˈmɪnɪk) adjective
Word Origin
C20: from hist(idine) + -amine
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for histamine

1913, "amine produced by the decomposition of histidine."

Online Etymology Dictionary, © 2010 Douglas Harper
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histamine in Medicine

histamine his·ta·mine (hĭs'tə-mēn', -mĭn)
A physiologically active depressor amine found in plant and animal tissue, derived from histidine by decarboxylation and released from cells in the immune system as part of an allergic reaction. It is a powerful stimulant of gastric secretion, constrictor of bronchial smooth muscle, and vasodilator.

his'ta·min'ic (-mĭn'ĭk) adj.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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histamine in Science
An organic compound found widely in animals and plants that in humans and other mammals is released as part of the body's immune response, causing physiological changes including dilation of the blood vessels, contraction of smooth muscle (as in the airways), and increased gastric acid secretion. The itching and sneezing typical of respiratory allergies are caused by the release of histamine. Chemical formula: C5H9N3
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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