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Proton Pump Inhibitor (PPI) Pregnancy: Generally considered safe. Omeprazole most studied in pregnancy.

Omeprazole / Lansoprazole (LPR)

Brand names: Losec (omeprazole), Zoton (lansoprazole)

Adult dose

Dose: Omeprazole 20–40 mg twice daily or Lansoprazole 30 mg twice daily for 8–16 weeks (LPR)
Route: Oral (before meals, 30–60 minutes before eating)
Frequency: Twice daily (LPR requires higher frequency than GORD)
Max: 40 mg twice daily (omeprazole); 60 mg/day (standard GORD use)
Laryngopharyngeal Reflux (LPR): 2× daily PPI for 16 weeks minimum. Standard GORD: 20 mg OD. H. pylori eradication triple therapy: 20 mg BD + clarithromycin 500 mg BD + amoxicillin 1 g BD for 7 days.

Paediatric dose

Dose: 0.7 mg/kg
Route: Oral
Frequency: Once daily
Max: 20 mg/day (children <10 kg); 40 mg/day (≥20 kg)
1–11 years: 0.7–1.4 mg/kg OD (max 20 mg OD for <10 kg, up to 20 mg OD for 10–20 kg). ≥12 years: adult dose. Omeprazole dispersible tablets available for younger children.

Dose adjustments

Renal

No dose adjustment required.

Hepatic

Max 20 mg/day in severe hepatic impairment.

Paediatric weight-based calculator

1–11 years: 0.7–1.4 mg/kg OD (max 20 mg OD for <10 kg, up to 20 mg OD for 10–20 kg). ≥12 years: adult dose. Omeprazole dispersible tablets available for younger children.

Clinical pearls

  • LPR requires TWICE DAILY dosing (unlike GORD where once daily usually sufficient)
  • Twice-daily dosing: take 30–60 min before breakfast and 30–60 min before evening meal
  • H. pylori eradication: use clarithromycin-based triple therapy (7 days) or bismuth quadruple therapy
  • Step-down after H. pylori eradication — confirm eradication with urea breath test 4 weeks after stopping
  • Review long-term PPI use annually — deprescribe if no longer indicated

Contraindications

  • Hypersensitivity to PPIs
  • Concomitant use with rilpivirine, atazanavir, nelfinavir

Side effects

  • Headache and GI upset
  • Hypomagnesaemia (prolonged use)
  • Osteoporosis and fractures (prolonged use)
  • Clostridium difficile (increased risk with prolonged use)
  • Hyponatraemia
  • Subacute cutaneous lupus erythematosus (rare)

Interactions

  • Clopidogrel — omeprazole reduces antiplatelet effect (use lansoprazole/pantoprazole instead)
  • Methotrexate — high-dose PPIs may increase MTX levels
  • Warfarin — increased INR in some patients
  • Rilpivirine, atazanavir — contraindicated (reduced absorption)

Monitoring

  • Symptom response
  • Serum magnesium (prolonged use)
  • Bone density (long-term use)
  • H. pylori eradication if indicated

Reference: BNFc; BNF; NICE CG184; British Society of Gastroenterology H. pylori guidelines. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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