Question

What are antihistamines

Answer 1

Histamines is an allergy which causes symptoms such as sneezing and excessive nasal secretions of allergic reactions. Thus antihistamines are the compounds used by chemists in various medicinal products which tends to block the effect of histamines and reduces the allergic reactions such as runny nose, watery eyes and sneezing. 

Answer 2

Hey !!

The drugs which interfere with the natural action of histamine by completing with histamine for binding of receptor where histamine exerts its effect are called antihistamine.

Example :- Terfenadine , brompheniramine etc.

Hope it helps you !