Lansoprazol Viatris (Lansoprazole)

Lansoprazole is a proton pump inhibitor indicated for several acid‑related gastrointestinal disorders.

• Gastro‑oesophageal reflux disease (GERD): provides symptomatic relief and promotes healing of esophageal irritation.
• Erosive esophagitis: heals erosive lesions and prevents recurrence.
• Peptic ulcer disease: promotes ulcer healing and reduces recurrence risk.
• Helicobacter pylori eradication (in combination therapy): enhances eradication rates when used with antibiotics.
• Zollinger‑Ellison syndrome: controls excessive gastric acid secretion associated with gastrin‑producing tumors.

• Lansoprazole selectively and irreversibly inhibits the H+/K+ ATPase enzyme (the gastric proton pump) located on the secretory surface of gastric parietal cells. By blocking this final step of acid production, it markedly reduces both basal and stimulated gastric acid secretion, leading to an increase in gastric pH and allowing ulcer healing and symptom relief.

Lansoprazole may cause a range of adverse reactions, from mild to serious.

Common Side Effects

• Headache: mild to moderate intensity.
• Diarrhea: loose stools occurring during treatment.
• Nausea: feeling of stomach upset.
• Abdominal pain: discomfort in the upper abdomen.
• Flatulence: increased gas.
• Constipation: reduced bowel movements.

Serious or Rare Side Effects

• Severe allergic reaction (anaphylaxis): swelling, rash, difficulty breathing.
• Clostridium difficile infection: severe diarrhea and colitis.
• Low magnesium levels (hypomagnesemia): muscle cramps, irregular heartbeat.
• Liver enzyme elevation: signs of hepatic dysfunction.
• Stevens‑Johnson syndrome or toxic epidermal necrolysis: severe skin reactions.
• Interstitial nephritis: kidney inflammation presenting with fever and rash.

Before prescribing Lansoprazol Viatris, clinicians should consider several safety aspects.

• Assess renal function: adjust use in patients with severe renal impairment.
• Monitor magnesium levels: prolonged therapy may cause hypomagnesemia.
• Evaluate for H. pylori infection: confirm eradication after combination therapy.
• Use with caution in the elderly: increased susceptibility to adverse effects.
• Avoid concomitant use with drugs that require gastric acidity for absorption unless medically necessary.
• Store at ambient temperature: keep in the original container, protect from moisture and direct sunlight.

Lansoprazole can affect the pharmacokinetics of several medicines.

Major Interactions (Avoid)

• Clopidogrel: reduced antiplatelet effect, increasing cardiovascular risk.
• Atazanavir: decreased antiviral efficacy due to reduced gastric acidity.
• HIV protease inhibitors (e.g., ritonavir): lowered plasma concentrations.

Moderate Interactions (Monitor Closely)

• Warfarin: possible increase in INR, requiring closer monitoring.
• Phenytoin: reduced serum levels, may diminish seizure control.
• Digoxin: increased serum concentration, risk of toxicity.
• Methotrexate: elevated levels, especially with high‑dose regimens.