Which of the following statements about histamines and antihistamines is NOT true?

A) A chief side effect of antihistamines is sedation.
B) Stimulation of the H1 histamine receptors plays a major role in the development of anaphylaxis.
C) Although asthma attacks can be caused by allergens, antihistamines should not be administered as a treatment.
D) There are antagonists for both H1 and H2 histamine receptor sites.

B