This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
Which of the following H1 blocker has high anticholinergic activity 
Select and explain. 
A. Cetirizine, B. Chlorpheneramine, C. Fexofenadine, D. Astemizole
B: Chlorpheneramine
Answer: B: Chlorpheneramine 
Explanation: Cetirizine and fexofenadine did not antagonize cholinergic responses. Chlorphenamine, also known as chlorpheniramine, is an antihistamine used to treat the symptoms of allergic conditions such as allergic rhinitis. It is taken by mouth. Onset is within 6 hours and effects last for about a day. Refer kDT 7/e p164