Ulcers

Question 1

Proton pump inhibitors

Answer 1

Omeprazole
Lansoprazole
Pantoprazole
Esomeprazole
Rabeprazole

Question 2

PPIs can lead to the toxicity of which drugs? How?

Answer 2

Cyclosporine, Warfarin, Diazepam. By reducing their metabolism because it is metabolised by the same enzymes responsible for their metabolism.

Question 3

Adverse effects of PPIs

Answer 3

GI troubles
Vit B12 deficiency
Subacute myopathy
Arthralgia
Hypergastrinemia

Question 4

How do PPIs cause Vit. B12 deficiency?

Answer 4

The vitamins need acid for absorption. Prolonged use will impair the process.

Question 5

What is the effect of hypergastrinemia?

Answer 5

Rebound gastric acid secretion
Gastrointestinal carcinoid tumours

Question 6

What are the clinically administered H2 antagonists?

Answer 6

Cimetidine
Ranitidine
Famotidine
Nizatidine

Question 7

Classes of drugs used to manage ulcers (8)

Answer 7

PPIs
H2 receptor antagonists
Muscarine receptor antagonists
Antacids

Prostaglandin analogues
Sucralfate
Colloidal bismuth compounds
Carbenoxolone

Question 8

Examples of Muscarine receptor antagonists

Answer 8

Pirenzepine
Telenzepine

Question 9

Some antacids stimulate PG synthesis. True or false?

Answer 9

True

Question 10

Adverse effects of M3 receptor antagonists

Answer 10

Xerostomia
Constipation
Blurred vision
Dyspepsia
Cognitive impairment

Question 11

Antacid examples

Answer 11

• Sodium bicarbonate
• Calcium carbonate
• Aluminium hydroxide
• Magnesium hydroxide

Question 12

What drugs are contraindicated in the use of antacids? Why?

Answer 12

Tetracycline and iron. The antacids impair the absorption of other drugs.

Question 13

Why is sucralfate preferred to PPIs in treatment of ulcers in critically ill patients?

Answer 13

Because increased gastric pH may be a factor in the development of nosocomial pneumonia in critically ill patients

Question 14

Why should sucralfate be avoided in patients with renal failure

Answer 14

Because some aluminium is absorbed

Question 14

Why should sucralfate be avoided in patients with renal failure

Answer 14

Because some aluminium is absorbed

Question 15

Sucralfate should be taken at least 2 hours after the administration of other drugs as phenytoin and digoxin. Why?

Answer 15

It forms a viscous layer in the stomach that may inhibit the absorption of drugs

Question 16

Prostaglandins inhibit histamine-stimulated gastric acid secretion. True or false?

Answer 16

True

Question 17

Which class of anti-ulcer agents would you use as a component of quadruple therapy to heal H. pylori ulcers?

Answer 17

Bismuth subsalicylate

Question 18

Bismuth subsalicylate MOA

Answer 18

• Coats ulcers and erosions protecting them from acid and pepsin
• Increases prostaglandin and bicarbonate production

Question 19

Therapeutic uses of bismuth subsalicylate

Answer 19

Dyspepsia
Acute diarrhoea

Question 20

Adverse reactions of carbenoxolone

Answer 20

It has aldosterone like action and may cause:
1- Sodium retention
2- Hypokalemia
3- Oedema
4- Exacerbates hypertention

Question 21

What is the role of somatostatin in gastric acid production?

Answer 21

Increased gastric pH reduces somatostatin release. Acidification stimulates gastrin release in a negative feedback loop. It is less in H. pylori patients, leading to excess gastrin and acid release.

Question 22

At what pH is somatostatin release stimulated?

Answer 22

3

Question 23

Metabolite of PPI

Answer 23

Tetracyclic sulphenamide/sulfenic acid