Peptic Ulcer and Drug Therapy

Peptic Ulcer

• Clinical Features:
  • Symptoms and signs: Epigastric pain and tenderness, anorexia, nausea and vomiting, hemorrhage.
  • Endoscopy.
  • Presence of H. pylori: Diagnosis via endoscopic biopsy, serological tests, and urea breath test.

Goals of Therapy

• Relief of pain.
• Promotion of healing.
• Prevention of recurrence.

Drug Therapy: Antacids

• Mechanism of Action: Neutralization of HCl, relief of pain, elevation of pH decreasing pepsin activity, some increase in prostaglandins and eradication of H. pylori.

Types of Antacids

• Chemical Antacids: Examples include sodium bicarbonate and calcium carbonate.
• Physical Antacids: Act by absorbing HCl and pepsin and have a demulcent effect on the ulcer, e.g., gastric mucin.

Anti-Secretory Drugs

• Mechanism of Action: Inhibit secretion of gastric HCl.

• Types of Anti-Secretory Drugs:

  • Anti-Muscarinic Drugs: Examples include pirenzepine and telenzepine (selective M1 blockers) to decrease acidity.
  • Gastrin Antagonists: Example is proglumide, a gastrin-receptor blocker.
  • Prostaglandins: Example is misoprostol, useful in treatment of NSAID-induced peptic ulcers.

H2 Blockers (e.g., Cimetidine)

• Pharmacodynamics: Selective competitive blocker of histamine H2 receptors, reducing gastric acidity.
• Side Effects: Sudden stop, recurrence of the ulcer, bleeding, GIT upsets, constipation or diarrhea, hypersensitivity reactions (skin rash and itching), affect liver and kidney, decrease hepatic blood flow.

Ranitidine (another H2 blocker)

• Pharmacodynamics: Similar to cimetidine but with longer duration of action and potentially stronger effect (5-10 times).
• Side Effects: Similar to cimetidine but possibly safer.

Proton Pump Inhibitors (e.g., Omeprazole, Lansoprazole, Pantoprazole)

• Mechanism of Action: Activated in the stomach's acidic environment, acting as irreversible inhibitors of H+/K+ ATPase enzyme.
• Therapeutic Uses: Peptic ulcers (drug of choice), gastroesophageal reflux disorder (GERD).
• Side Effects: CNS effects (headache, dizziness, drowsiness), GIT effects (nausea, diarrhea, abdominal colic), skin rash.

Mucosal Protectives (e.g., Prostaglandins)

• Mechanism of Action: Increase mucus secretion, increase bicarbonate secretion, increase blood supply to the mucosa, decrease HCL secretion, promote healing of ulcers, and prevent gastric ulcers induced by analgesics.
• Side Effects: None specified in the provided text.

Contraindications and Additional Side Effects

• Oxytocic effect: Contraindicated in pregnancy (causes abortion).
• Nausea and abdominal pain.

Test your knowledge on peptic ulcers, their clinical features, and the goals of therapy. This quiz covers drug therapy including antacids and anti-secretory drugs, as well as their mechanisms of action. Ideal for students and professionals in healthcare who want to deepen their understanding of gastrointestinal disorders.