Lansoprazole Generics [uk] (Lansoprazole)

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

• Gastro‑oesophageal reflux disease (GERD): reduces reflux symptoms and promotes healing of the oesophageal lining.
• Peptic ulcer disease: facilitates ulcer healing by lowering gastric acidity.
• Helicobacter pylori eradication regimens: enhances the effectiveness of antibiotic combinations in H. pylori infection.
• Zollinger‑Ellison syndrome: controls excessive gastric acid production associated with gastrin‑secreting tumours.

• Lansoprazole selectively and irreversibly inhibits the H+/K+ ATPase enzyme (gastric proton pump) located on the secretory surface of parietal cells. By blocking this final step of acid secretion, it markedly reduces both basal and stimulated gastric acid output, thereby increasing gastric pH and allowing mucosal healing in acid‑related diseases.

Adverse reactions may occur with lansoprazole use.

Common Side Effects

• Headache: mild to moderate pain often transient.
• Diarrhoea: loose stools, usually self‑limiting.
• Abdominal pain: discomfort or cramping in the stomach area.
• Nausea: feeling of sickness, sometimes with vomiting.
• Flatulence: increased gas production.
• Constipation: reduced bowel movements.

Serious or Rare Side Effects

• Severe allergic reactions: rash, swelling, or anaphylaxis.
• Clostridioides difficile infection: severe colitis with watery diarrhoea.
• Liver enzyme elevation: signs of hepatic stress.
• Low magnesium levels: muscle cramps, irregular heartbeat.
• Pancreatitis: upper abdominal pain with nausea.
• Stevens‑Johnson syndrome: blistering skin eruptions.

Before prescribing lansoprazole, consider the following precautions.

• Renal or hepatic impairment: assess function and adjust therapy if needed.
• Elderly patients: monitor for increased risk of fractures and infections.
• Long‑term use: evaluate for vitamin B12 deficiency and bone health.
• Concomitant medications: review for potential interactions, especially with antiplatelet agents.
• Pregnancy and breastfeeding: weigh benefits against potential risks; consult obstetric guidance.
• Store at room temperature: keep in the original container, protect from moisture and direct sunlight.

Lansoprazole may interact with several medicines.

Major Interactions (Avoid)

• Atazanavir or other HIV protease inhibitors: markedly reduced antiviral absorption.
• Warfarin: increased anticoagulant effect, risk of bleeding.
• Methotrexate: elevated serum levels, potential toxicity.

Moderate Interactions (Monitor Closely)

• CYP2C19 substrates such as phenytoin: altered plasma concentrations.
• Antifungal agents like ketoconazole: decreased efficacy due to reduced absorption.
• Oral contraceptives: possible reduction in contraceptive effectiveness.