“H1.”

The following 2 entries include the term H1..

H1 antagonist

noun

: any of numerous drugs (such as fexofenadine or loratadine) that bind competitively with histamine to H1 receptors on cell membranes and are used to relieve allergic symptoms and variously as sedatives, antiemetics, and anticholinergics

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H1 receptor

noun

: a receptor for histamine on cell membranes that modulates the dilation of blood vessels and the contraction of smooth muscle see h1 antagonist

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