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33. Histamine, antihistaminic drugs: Difference between revisions

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(Created page with "== Histamine == Histamine is a basic amine that is formed from histidine by ''histidine decarboxylase''. Mast cells, basophils, histamininergic neurons and enterochromaffin cells produce it. Mast cells are especially abundant in the respiratory tract, <abbr>GI</abbr> tract and skin. Mast cells have granules that contain histamine and other compounds. These granules are exocytosed (called degranulation) when the <abbr>IgE</abbr> molecules bound to the cell bind to an ant...")
 
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* Sedation and somnolence
* Sedation and somnolence


Sedation is the most important side effect of first generation antihistamines, and it’s this side effects which makes them inferior to second generation antihistamines for allergy. ''In fact, diphenhydramine is so famous for it’s significant somnolent side effects that there are memes about it.''
Sedation is the most important side effect of first generation antihistamines, and it’s this side effects which makes them inferior to second generation antihistamines for allergy. ''In fact, diphenhydramine is so famous for it’s significant somnolent side effects that there are memes'' <ref>https://www.google.com/search?q=benadryl+meme&tbm=isch</ref>''about it.''


First generation H1 antagonists also block muscarinic receptors and therefore have anticholinergic side effects, like:
First generation H1 antagonists also block muscarinic receptors and therefore have anticholinergic side effects, like: