Lansoprazole Eg (Lansoprazole)

Lansoprazole is a proton pump inhibitor that reduces gastric acid secretion and is indicated for several acid‑related gastrointestinal conditions.

• Gastro‑oesophageal reflux disease (GERD): alleviates heartburn and esophageal irritation by maintaining higher gastric pH.
• Peptic ulcer disease: promotes ulcer healing and prevents recurrence by suppressing acid production.
• Zollinger‑Ellison syndrome: controls hyper‑secretion of gastric acid in this rare endocrine disorder.
• Erosive esophagitis: facilitates mucosal healing by reducing acid exposure.
• Helicobacter pylori eradication therapy: used in combination with antibiotics to improve eradication rates.

• Lansoprazole selectively and irreversibly inhibits the H+/K+ ATPase enzyme (the gastric proton pump) located on the secretory surface of parietal cells in the stomach. By binding covalently to the cysteine residues of the pump, it blocks the final step of acid secretion, and thereby leading to a prolonged reduction of gastric acidity irrespective of stimulation by histamine, gastrin or acetylcholine.

Lansoprazole may cause a range of adverse reactions, which are classified by frequency and severity.

Common Side Effects

• Headache: mild to moderate pain often transient.
• Diarrhea: loose stools occurring during treatment.
• Nausea: feeling of stomach discomfort or urge to vomit.
• Abdominal pain: cramping or discomfort in the stomach area.
• Flatulence: increased intestinal gas.
• Constipation: difficulty passing stools.

Serious or Rare Side Effects

• Severe allergic reaction (anaphylaxis): swelling, rash, difficulty breathing.
• Low magnesium levels (hypomagnesemia): muscle cramps, irregular heartbeat.
• Clostridioides difficile infection: severe diarrhea, abdominal pain.
• Bone fracture risk: increased incidence of hip or wrist fractures with long‑term use.
• Liver enzyme elevation: signs of hepatitis such as jaundice.

Before prescribing Lansoprazole, clinicians should consider several precautionary measures to ensure safe use.

• Assess renal function: dose adjustment may be needed in severe impairment.
• Evaluate for osteoporosis: long‑term therapy can affect calcium absorption.
• Review concomitant medications: potential for reduced efficacy of drugs requiring acidic pH.
• Monitor for infections: prolonged acid suppression may increase risk of gastrointestinal infections.
• Use cautiously in pregnancy: safety data are limited; weigh benefits against potential risks.
• Store at room temperature: keep below 25 °C, protect from moisture and light in the original packaging.

Lansoprazole can interact with other medicines, altering their effectiveness or safety.

Major Interactions (Avoid)

• Antifungal agents (ketoconazole, itraconazole): reduced absorption due to increased gastric pH.
• HIV protease inhibitors (atazanavir, nelfinavir): decreased plasma levels, compromising antiviral activity.

Moderate Interactions (Monitor Closely)

• Clopidogrel: reduced activation, potentially lowering antiplatelet effect.
• Warfarin: possible increase in INR, requiring closer monitoring.
• Digoxin: increased serum concentration, may need dose adjustment.
• Methotrexate: higher levels may occur, especially with high doses.