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diphenhydramine hydrochloride

The hydrochloride salt form of diphenhydramine, an ethanolamine and first-generation histamine antagonist with anti-allergic activity. Diphenhydramine hydrochloride competitively blocks H1receptors, thereby preventing the actions of histamine on bronchial smooth muscle, capillaries, and gastrointestinal (GI) smooth muscle. This prevents histamine-induced bronchoconstriction, vasodilation, increased capillary permeability, and GI smooth muscle spasms.
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US brand name:Benadryl
SK-Diphenhydramine
Foreign brand name:Bendylate
Eldadryl
NSC code:33299
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