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Proton Pump Inhibitor (PPI) Pregnancy: Compatible — PPIs considered safe in pregnancy when clinically indicated.

Lansoprazole

Brand names: Zoton FasTab

Adult dose

Dose: GORD/peptic ulcer: 30mg OD for 4–8 weeks. Maintenance GORD: 15–30mg OD. H. pylori eradication: 30mg BD (with amoxicillin 1g BD + clarithromycin 500mg BD) × 7 days. NSAID-associated ulcer: 15–30mg OD.
Route: Oral
Frequency: Once daily (30 min before breakfast)
Max: 60mg BD in Zollinger-Ellison syndrome
Orodispersible tablets (FasTab) dissolve on tongue — useful when swallowing difficult. Take 30 min before first meal. If no response to 30mg, increase to 60mg OD before escalating investigations.

Paediatric dose

Dose: 0.5 mg/kg
Route: Oral
Frequency: Once daily
Max: 30mg OD
BNF for Children: 1–11 years: 0.5–1mg/kg OD (max 15mg); 12–17 years: 15–30mg OD. Not licensed <1 year. Source: BNF for Children 2024.

Dose adjustments

Renal

No dose adjustment required.

Hepatic

Reduce dose and frequency in moderate–severe hepatic impairment. Max 30mg OD in moderate disease.

Paediatric weight-based calculator

BNF for Children: 1–11 years: 0.5–1mg/kg OD (max 15mg); 12–17 years: 15–30mg OD. Not licensed <1 year. Source: BNF for Children 2024.

Clinical pearls

  • Preferred PPI in patients with dysphagia — orodispersible (FasTab) formulation dissolves on tongue without water.
  • H. pylori eradication: check local clarithromycin resistance rates. Quadruple therapy (PPI + bismuth + tetracycline + metronidazole) if clarithromycin resistance >20%.
  • Long-term PPI: annual review of indication. Hypomagnesaemia risk — check Mg²⁺ at 3 months and annually.
  • Like all PPIs, use pantoprazole (not lansoprazole) in patients on clopidogrel — less CYP2C19 inhibition.

Contraindications

  • Concomitant rilpivirine, atazanavir, or nelfinavir (PPI reduces antiretroviral absorption — avoid combination)

Side effects

  • Headache, diarrhoea, nausea (all common)
  • Hypomagnesaemia (prolonged use — check Mg²⁺)
  • C. difficile infection (increased risk with long-term use)
  • Vitamin B12 deficiency (long-term)
  • Interstitial nephritis (rare)
  • Fundic gland polyps (long-term, benign)

Interactions

  • Clopidogrel: lansoprazole inhibits CYP2C19 — use pantoprazole instead
  • Methotrexate: PPIs reduce clearance — monitor toxicity
  • Atazanavir / rilpivirine: reduced antiretroviral absorption — avoid
  • Warfarin: may increase INR — monitor

Monitoring

  • Symptoms
  • H. pylori eradication test (4 weeks after treatment)
  • Mg²⁺ (long-term use)
  • B12 (long-term)

Reference: BNFc; BNF 90; NICE CG17 GORD; NICE NG12 H. pylori. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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