Which action below is affected by an antihistamine?
A)blood vessel dilation
B)phagocytosis of antigens
C)MHC presentation by macrophages
D)the secondary immune response
E)clonal selection by antigens

Question

Quizplus · Accepted Answer

Antihistamines work by blocking the action of histamine, a chemical released by the immune system as part of an allergic reaction. Histamine causes blood vessels to dilate, leading to inflammation and symptoms such as itching and swelling. By blocking histamine, antihistamines can reduce these symptoms.

Which Action Below Is Affected by an Antihistamine