Treatment of Peptic Ulcer

Question 1

Eradication of H. pylori

Triple therapy

Answer 1

Triple Therapy:

1. ​PPI (omeprazole), metronidazole/amoxicillin and clarythromycin
2. Clarythromycin, tetracycline, ompeprazole
3. H₂ receptor antagonist (rantidine), bisthmus sunsalicyclate, clarythromycin

Question 2

Eradication of H. pylori

Quadruple therapy

Answer 2

Quadruple therapy:

1. ​Bisthmus subsalicyclate for mucosal protection, metronidazole tetracyline PPI
2. Reistant case: PPI, Amoxicillin, clarythromycin metronidazole

Question 3

What happens if a single therapy is used to eradicate H pylori

Answer 3

• less effective
• antimicrobial resistance

therefore: use a combination given twice daily for 2 weeks

Question 4

PPI

overview

Answer 4

• inhibit acid secretion by > 90%
• More effective at healing ulcers than H2 receptor anatagonists
• Longer duration of action than H2 receptor anatagonists
  
  • ​This is becuase they inhibit the H/K-ATPase pump
• Once daily 30 min before breakfast or largest meal

Question 5

PPI

Uses

Answer 5

• Treat peptic ulcer
• Reflux esophagitis
• Part of treating H. pylori
• Zollinger Ellison syndrome

Question 6

PPI

Drug interactions

Answer 6

Ompeprazole inhibits CYP450 therefore reduces metabolism of warfarin and phenytoin

Question 7

H₂ Receptor Antagonists

Include

Answer 7

1. Famotidine
2. Cimetidine

Question 8

H2 Receptor Antagonists

MOA

Answer 8

Competitivily and reversibly block histamine induced acid secretion by parietal cells

• less than PPI

Question 9

H2 Receptor Antagonists

PHARMACOKINETICS

Answer 9

Well absorbed orally

Question 10

H2 Receptor Antagonists

Adverse effects

Answer 10

Cimitidine:

Acts as nonsteroidal antiandrogen →gynecomastia and galactorrhea

Question 11

Cimitidine drug interactions

Answer 11

• inhibits CYP450 and reduce meabolism of warfarin and phenytoin
• Reduce efficacy of drugs that require an acidic enviornment for absorption like ketoconazole

Question 12

Antimuscarinic Agents

Answer 12

Dicyclomine:

• Adjucnt in Zollinger Ellison syndrome
• Those who are refractory to other treatments
  
  • Adverse effect
    
    • carduac arrythmia
    • dry mouth
    • constipation
    • urinary retention

Question 13

Antacids

Answer 13

• weak bases
• react with gastric acid to form water and a salt→decreasing acidity
• Reduce pepsin activity
  
  • Pepsin in inactive at pH>4

Question 14

Commonly used antacids

Answer 14

• MgOH
• Milk of magnesia
• Aluminum OH

relieve pain and provide symptomatic relief

avoid other drugs

Question 15

Cytoprotective Compounds

Answer 15

1. Bismuth subsalicylate
2. Sucralfate
3. Misoprostol

Question 16

Bismuth subsalicylate

Answer 16

• combination regimen to treat h pylori infection of peptic ucler
  
  • antimicrobial
• Coat ulcer base→protective barrier and increase bicarb and mucous secretion
• Inhibit pepsin
• BLACK TONGUE AND STOOL

Question 17

Sucralfate

Answer 17

• forms complex gels with mucus
  
  • decrease degradation of mucous by acid and pepsin
• Stimulate PG release and bicarb from mucous
• Forms viscous paste in acidic enviornment
  
  • ​Efficacy reduced by antacids and H₂ antagonists
• Orally to heal duodenal ulcers and prevent their recurrence

Question 18

Misoprostol

Answer 18

• Inhibits gastric acid secretion
• Increase secretion of mucous and bicarb
• ONLY used to prevent gastric damage that occurs with chronic use of NSAIDs
• Uterine contractions therefore contraindicated in pregnancy
• Causes diarrhea and abdominal cramps