Last reviewed 2026-04-22 · How we verify

Lansoprazole Pill

Lansoprazole inhibits the proton pump in gastric parietal cells, reducing gastric acid secretion.

Lansoprazole inhibits the proton pump in gastric parietal cells, reducing gastric acid secretion. Used for Gastroesophageal reflux disease (GERD), Peptic ulcer disease, Zollinger-Ellison syndrome.

At a glance

Mechanism of action

Lansoprazole is a proton pump inhibitor (PPI) that irreversibly binds to and inactivates the H+/K+-ATPase enzyme in the stomach's parietal cells. This blocks the final step of gastric acid production, significantly reducing intragastric acidity. It is used to treat acid-related disorders by maintaining elevated gastric pH.

Approved indications

• Gastroesophageal reflux disease (GERD)
• Peptic ulcer disease
• Zollinger-Ellison syndrome
• Prevention of NSAID-induced ulcers

Common side effects

• Headache
• Diarrhea
• Abdominal pain
• Nausea
• Constipation

Key clinical trials

• Neuroregulators for the Treatment of Diseases Associated With Esophageal-brain-gut Axis Communication Abnormalities. (NA)
• Medicine-induced Cardiac Hemodialysis on COVID-19 (PHASE4)
• Effect of Proton Pump Inhibitors on Endothelial Function (PHASE1)
• The Effects of Dexlansoprazole for the Treatment of Throat-Related Reflux (NA)
• The Effect of Proton Pump Inhibition on Palpitations (PHASE4)
• Fentanyl Administered Intraorally for Rapid Treatment of Orthopedic Pain (PHASE1, PHASE2)
• Lansoprazole to Treat Children With Asthma (PHASE4)
• Safety and Efficacy of Lansoprazole 30mg Twice Daily in Treatment of Laryngitis Associated With Gastroesophageal Reflux (PHASE4)

Primary sources

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