An antihistamine is a drug which serves to reduce or eliminate effects mediated by histamine, an endogenous chemical mediator released during allergic reactions, through action at the histamine receptor. Only agents where the main therapeutic effect is mediated by negative modulation of histamine receptors are termed antihistamines - other agents may have antihistaminergic action but are not true antihistamines.
In common use, the term antihistamine refers only to H1-receptor antagonists, also known as H1-antihistamines. It has been discovered that these H1-antihistamines are actually inverse agonists at the histamine H1-receptor, rather than antagonists per se. (Leurs, Church & Taglialatela, 2002)
Pharmacology
In allergic reactions an
allergen (a type of
antigen) interacts with and cross-links surface IgE
antibodies on
mast cells and
basophils. Once the mast cell-antibody-antigen complex is formed, a complex series of events occurs that eventually leads to cell-degranulation and the release of histamine (and other chemical mediators) from the mast cell or basophil. Once released, histamine can react with local or widespread tissues through
histamine receptors.
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Allergy Treatments
Antihistamines - Twitter SearchAnyone? RT @parsnipnose3000: If anyone knows of a cure/treatment for Cold Urticaria that doesn't involve antihistamines, please let me know.andrew_paradigm (Andrew Elliott) Wed, 04 Nov 2009 14:50:12 -0000
Anyone? RT @parsnipnose3000: If anyone knows of a cure/treatment for Cold Urticaria that doesn't involve antihistamines, please let me know.
If anyone knows of a cure/treatment for Cold Urticaria that doesn't involve antihistamines, please let me know. please RTparsnipnose3000 (parsnipnose3000) Wed, 04 Nov 2009 14:36:15 -0000
If anyone knows of a cure/treatment for Cold Urticaria that doesn't involve antihistamines, please let me know. please RT
@allieuk5 Aw you poor thing!Sending you get well wishes+some antihistamines.Better to get flu maybe?Now how are we gonna get Ry's attention?alfiewozere (maggie may) Wed, 04 Nov 2009 10:58:36 -0000
@allieuk5 Aw you poor thing!Sending you get well wishes+some antihistamines.Better to get flu maybe?Now how are we gonna get Ry's attention?
ok either the antihistamines are finally working or the office a/c being turned off has finally given my nose some reprievechibimoon (addie.) Wed, 04 Nov 2009 07:13:58 -0000
ok either the antihistamines are finally working or the office a/c being turned off has finally given my nose some reprieve
fucking antihistamines not workingchibimoon (addie.) Wed, 04 Nov 2009 06:28:19 -0000
fucking antihistamines not working
My body celebrates my 21st birthday by suddenly breaking out into hives. Required a 1 am run to price chopper for antihistamines. lamealemerson (Andrew Emerson) Wed, 04 Nov 2009 06:16:31 -0000
My body celebrates my 21st birthday by suddenly breaking out into hives. Required a 1 am run to price chopper for antihistamines. lame
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Antihistamines - A brief overview of this group of medicines which help with the symptoms of allergies.
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Prescription Antihistamine Database - Information about medications available by prescription in the U.S., arranged by drug name.
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