Pharmacology · single question
A drug like famotidine (Pepcid) has which mechanism of action?
Show answer and explanation
Correct answer: A. H2 receptor antagonist
- A. Correct. Famotidine (Pepcid) and ranitidine belong to the H2 receptor antagonist class. They competitively block histamine H2 receptors on gastric parietal cells, reducing acid secretion.
- B. H1 receptor antagonists are antihistamines used for allergy (e.g., diphenhydramine, cetirizine), not for acid suppression.
- C. H2 agonists would stimulate acid production — the opposite of the therapeutic goal.
- D. H1 agonists are not clinically used and would provoke allergic responses.