Antihistamines that are H₁-antagonists are least effective at competitively blocking the effect of histamine at which of the following sites?

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Quizplus · Accepted Answer

Because other autocoids are also released in an anaphylactic reaction,antihistamines are not effective in counteracting all the bronchoconstriction during that reaction.The antihistamines block the dilation of the vascular smooth muscle that histamine produces.By blocking capillary permeability produced by histamine,less tissue edema occurs from the transport of the serum into the intracellular spaces.Antihistamines can suppress the itching and pain associated with this histamine-mediated reaction at the cutaneous nerve endings.

Antihistamines That Are H₁-Antagonists Are Least Effective at Competitively Blocking