Question

Both antacid and anti allergic drugs are antihistamines but they cannot replace each other. Why?

Answer 1

Answer:

because the site of action are diffrent

Answer 2

Antihistamines are the drugs which control the allergy affects produced by histamine. Antacids are the substances which neutralise gastric acidity. Antihistamine do not affect the secretion of acid in the stomach and the reason is that both anti-allergic and antacid drugs work on different receptors.Read more on Sarthaks.com - https://www.sarthaks.com/199702/both-antacids-anti-allergic-drugs-antihistamines-they-cannot-replace-each-other-explain