B / 23 : Drugs Influencing Gastric Acid Seccretion, Protective Drugs Of Mucosa

Question 1

How is acid secretion in upper gastric ulcers?

Answer 1

The acid secretion is normal, with decreased defensive mechanisms

Question 2

How is acid secretion in distal, antral or duodenal ulcers?

Answer 2

Hypersecretion with increased aggressive factors

Question 3

What are the acid suppressing agents?

Answer 3

• Omeprazole
• Pantoprazole
• Famotidine

Question 4

Omeprazole, Pantoprazole
- MOA
- Effect
- Indication
- SE
- Pharmacokinetics
- ROA

Answer 4

• Proton pump inhibitor (PPI) in gastric parietal cells
• Inhibits gastric acid secretion
• For GERD, peptic ulcer disease, H.Pylori associated ulcers
• Long term treatment : hypergastrinemia, bacterial overgrowth, decreased B12 absorption
• Effects last up to 24h, full potential is reached within 3-4 days of treatment
• Oral, IV

Question 5

Dose of pantoprazole

Answer 5

1-2 x 20-40mg

Question 6

Famotidine
- MOA
- Effect
- Indication
- SE
- Pharmacokinetics
- ROA

Answer 6

• H2 receptor antagonist (Gs)
• Inhibits gastric acid production (indirect effect on H+ pump)
• For GERD, peptic ulcer disease, H.pylori associated ulcers
• Mild : diarrhea, headache…
• Duration of action : 12-24 hours
• Oral, parenteral - at bedtime

Question 7

Dose of famotidine

Answer 7

2x20mg or 1x40mg

Question 8

What are antacids?

Answer 8

Weak bases that neutralize gastric acid by reacting with protons

Question 9

What are the antacids?

Answer 9

• Mg(OH)2 : magnesium hydroxide
• Al(OH)3 : aluminium hydroxide

Question 10

Magnesium hydroxide and aluminium hydroxide
- MOA
- Effect
- indication
- SE

Answer 10

• Antiacids
• Slow onset, poorly absorbed from bowel
• Protects mucosa
• Mg : diarrhea, hypermagnesemia, Al: constipation, encephalopathy