PPIs

• The parietal cells release protons (positive hydrogen ions) during HCl production. It is called the proton pump and only PPIs stop the action of this pump (not H2 blockers or antacids)
• PPIs are the most effective drugs to suppress acid secretion
• Mechanism of action: inhibits the proton pump enzyme which generates gastric acid

  • prevents movement of hydrogen ions from parietal cells into the stomach
  • all gastric acid secretion is temporarily blocked until parietal cells synthesize new ATPase
• Examples:

  • omeoprazole (losec)
  • lansoprazole (prevacid)
  • esomeprazole (nexium)
  • pantoprazole (pantaloc)
  • dexlansoprazole (dexilant)
• Indications

  • short term treatment of active ulcers
  • GERD
  • erosive esophagitis
  • prevention of stress ulcer
  • failed response to H2 antagonists
  • treatment of H Pylori induced ulcers associated with antibiotics
• Contraindications

  • can increase risk C difficile infection = important to report diarrhea symptoms
  • drug allergy
  • well tolerated by older adults
  • liver failure (elevation of liver enzyme)
• Drug interaction

  • can reduce adverse effect of clopidogrel (antiplatelet) or can reduce its beneficial effects
• Adverse effect of short term use

  • generally little effect
  • diarrhea
  • nausea and vomiting
  • headache, dizziness, asthenia (weakness)
  • upper resp infections and pneumonia
• Adverse effect of long term therapy

  • fractures (decreased calcium absorption)
  • rebound acid hypersecretion
  • hypomagnesemia