H2 Antagonists GRADE A Q&A
H2 Antagonists - (correct answer)Histamine Type 2 (H2) Antagonists
• Reduce acid secretion
• All available over the counter in lower dosage forms
• Most popular drugs for treatment of acid-related disorders
H2 Antagonists: Drug Examples - (correct answer)• cimetidine (Tagamet)
• nizatidine (Axid)
• *famotidine (Pepcid)
• ranitidine (Zantac)
H2 Antagonists:
Mechanism of Action - (correct answer)• Block histamine at the (H2) receptors of acid-
producing parietal cells
• Production of hydrogen ions is reduced -> decreased production of HCl
H2 Antagonists: Effects - (correct answer)Suppressed acid secretion in the stomach
H2 Antagonists: Indications - (correct answer)• GERD: gastroesophageal reflux disease
• PUD: peptic ulcer disease
• Erosive esophagitis
• Adjunct therapy to control upper GI bleeding
• Pathologic gastric hypersecretory conditions
*H2 Antagonists: Adverse Effects - (correct answer)• Overall, very few adverse effects
• Cimetidine may induce impotence and gynecomastia
• May cause headaches, lethargy, confusion, diarrhea, urticaria, sweating, flushing,
other effects
H2 Antagonists - (correct answer)Histamine Type 2 (H2) Antagonists
• Reduce acid secretion
• All available over the counter in lower dosage forms
• Most popular drugs for treatment of acid-related disorders
H2 Antagonists: Drug Examples - (correct answer)• cimetidine (Tagamet)
• nizatidine (Axid)
• *famotidine (Pepcid)
• ranitidine (Zantac)
H2 Antagonists:
Mechanism of Action - (correct answer)• Block histamine at the (H2) receptors of acid-
producing parietal cells
• Production of hydrogen ions is reduced -> decreased production of HCl
H2 Antagonists: Effects - (correct answer)Suppressed acid secretion in the stomach
H2 Antagonists: Indications - (correct answer)• GERD: gastroesophageal reflux disease
• PUD: peptic ulcer disease
• Erosive esophagitis
• Adjunct therapy to control upper GI bleeding
• Pathologic gastric hypersecretory conditions
*H2 Antagonists: Adverse Effects - (correct answer)• Overall, very few adverse effects
• Cimetidine may induce impotence and gynecomastia
• May cause headaches, lethargy, confusion, diarrhea, urticaria, sweating, flushing,
other effects
