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Proton Pump Inhibitor (PPI) Pregnancy: Section 4.6 verbatim: 'Results from three prospective epidemiological studies (more than 1 000 exposed outcomes) indicate no adverse effects of omeprazole on pregnancy or on the health of the foetus/newborn child. Omeprazole can be used during pregnancy.' Breast-feeding: 'Omeprazole is excreted in breast milk but is not likely to influence the child when therapeutic doses are used.' Fertility: 'Animal studies with the racemic mixture omeprazole, given by oral administration do not indicate effects with respect to fertility.'

Omeprazole (Paediatric — GORD/Peptic)

Brand names: Losec, Mepradec

Omeprazole (paediatric — GORD/peptic) is a proton pump inhibitor used in children for gastro-oesophageal reflux disease, reflux oesophagitis and peptic ulcer disease, including as part of H. pylori eradication. This page covers its use for paediatric GORD and peptic disease.

Adult dose

Dose: 20 mg once daily for reflux oesophagitis and for symptomatic gastro-oesophageal reflux disease. Section 4.2 verbatim: 'Treatment of reflux oesophagitis The recommended dose is Losec 20 mg once daily. In most patients healing occurs within four weeks. For those patients who may not be fully healed after the initial course, healing usually occurs during a further four weeks treatment period. In patients with severe oesophagitis Losec 40 mg once daily is recommended and healing is usually achieved within eight weeks.' And: 'Treatment of symptomatic gastro-oesophageal reflux disease The recommended dose is Losec 20 mg daily. Patients may respond adequately to 10 mg daily, and therefore individual dose adjustment should be considered.'
Route: Oral. Section 4.2 verbatim: 'It is recommended to take Losec capsules in the morning, swallowed whole with half a glass of water. The capsules must not be chewed or crushed.'
Frequency: Once daily, in the morning. Review point, section 4.2 verbatim: 'If symptom control has not been achieved after four weeks treatment with Losec 20 mg daily, further investigation is recommended.'
Max: Not stated - this SPC states no maximum dose and no dose ceiling for reflux oesophagitis or symptomatic gastro-oesophageal reflux disease. The higher figures it gives are either an alternative dose for severe disease or belong to different indications, and are recorded in the notes rather than treated as a cap here.
SCOPE: this page is the paediatric omeprazole entry (name 'Omeprazole (Paediatric - GORD/Peptic)', specialty paediatrics and gi-hepatology) and its own adult block says 'Full adult dosing in GI section'. || OTHER ADULT INDICATIONS IN THE SAME SPC, section 4.2 verbatim - Duodenal ulcer: 'The recommended dose in patients with an active duodenal ulcer is Losec 20 mg once daily. In most patients healing occurs within two weeks... In patients with poorly responsive duodenal ulcer Losec 40 mg once daily is recommended and healing is usually achieved within four weeks.' Prevention of relapse of duodenal ulcer in H. pylori negative patients or where eradication is not possible: 'Losec 20 mg once daily. In some patients a daily dose of 10 mg may be sufficient. In case of therapy failure, the dose can be increased to 40 mg.' Gastric ulcer: 'Losec 20 mg once daily... In patients with poorly responsive gastric ulcer Losec 40 mg once daily is recommended and healing is usually achieved within eight weeks.' Prevention of relapse of gastric ulcer: 'Losec 20 mg once daily. If needed the dose can be increased to Losec 40 mg once daily.' NSAID-associated gastric and duodenal ulcers, treatment and prevention in patients at risk (age over 60, previous ulcer history, previous upper GI bleeding): 'Losec 20 mg once daily.' Long-term management of healed reflux oesophagitis: 'the recommended dose is Losec 10 mg once daily. If needed, the dose can be increased to Losec 20 mg to 40 mg once daily.' Zollinger-Ellison syndrome (a DIFFERENT indication - do not read its figures as a reflux ceiling): 'The recommended initial dose is Losec 60 mg daily... more than 90% of the patients maintained on doses of Losec 20 mg to 120 mg daily. When dose exceed Losec 80 mg daily, the dose should be divided and given twice daily.' Adult H. pylori eradication in peptic ulcer disease: 'Losec 20 mg + clarithromycin 500 mg + amoxicillin 1 000 mg, each twice daily for one week, or Losec 20 mg + clarithromycin 250 mg (alternatively 500 mg) + metronidazole 400 mg (or 500 mg or tinidazole 500 mg), each twice daily for one week or Losec 40 mg once daily with amoxicillin 500 mg and metronidazole 400 mg (or 500 mg or tinidazole 500 mg), both three times a day for one week.' || ELDERLY (section 4.2 verbatim): 'Dose adjustment is not needed in the elderly.' || INTERACTION-SPECIFIC CEILING, NOT A GENERAL MAXIMUM (section 4.4 verbatim): if atazanavir plus a proton pump inhibitor 'is judged unavoidable, close clinical monitoring (e.g. virus load) is recommended in combination with an increase in the dose of atazanavir to 400 mg with 100 mg of ritonavir; omeprazole 20 mg should not be exceeded.' || ADMINISTRATION FOR SWALLOWING DIFFICULTY (section 4.2 verbatim): 'Patients can open the capsule and swallow the contents with half a glass of water or after mixing the contents in a slightly acidic fluid e.g. fruit juice or applesauce, or in non-carbonated water. Patients should be advised that the dispersion should be taken immediately (or within 30 minutes) and always be stirred just before drinking and rinsed down with half a glass of water. Alternatively, patients can suck the capsule and swallow the pellets with half a glass of water. The enteric-coated pellets must not be chewed.'

Paediatric dose

Route: Oral - capsules swallowed whole with half a glass of water; for children who can drink or swallow semi-solid food the capsule may be opened and the enteric-coated pellets taken as described in the notes
Frequency: Once daily
Max: Not stated - the paediatric section gives weight-banded doses with an optional increase 'if needed', but never states a maximum dose or ceiling. The banded figures are set out in full in the notes.
WEIGHT-BANDED, NOT PER-KILOGRAM - dosePerKg is null because this SPC doses paediatric reflux by weight band, not by mg/kg; do not derive a per-kilogram figure from these bands. concentration is null because the sourced product is Losec Capsules 10mg, a capsule with no milligrams-per-millilitre strength; the previous prose concentration string on this page had no numeric mg/mL meaning. || CHILDREN OVER 1 YEAR OF AGE AND AT LEAST 10 kg - Treatment of reflux oesophagitis, and symptomatic treatment of heartburn and acid regurgitation in gastro-oesophageal reflux disease (section 4.2, verbatim table): at least 1 year of age, 10 to 20 kg - '10 mg once daily. The dose can be increased to 20 mg once daily if needed'; at least 2 years of age, over 20 kg - '20 mg once daily. The dose can be increased to 40 mg once daily if needed'. || DURATION (section 4.2 verbatim): 'Reflux oesophagitis: The treatment time is 4 to 8 weeks. Symptomatic treatment of heartburn and acid regurgitation in gastro-oesophageal reflux disease: The treatment time is 2 to 4 weeks. If symptom control has not been achieved after 2 to 4 weeks the patient should be investigated further.' || H. PYLORI DUODENAL ULCER, children and adolescents over 4 years of age, weight-banded, specialist-supervised - section 4.2 verbatim: 'The treatment should be supervised by a specialist.' 15 to 30 kg: 'Combination with two antibiotics: Losec 10 mg, amoxicillin 25 mg/kg body weight and clarithromycin 7.5 mg/kg body weight are all administered together two times daily for one week.' 31 to 40 kg: 'Combination with two antibiotics: Losec 20 mg, amoxicillin 750 mg and clarithromycin 7.5 mg/kg body weight are all administered two times daily for one week.' Over 40 kg: 'Combination with two antibiotics: Losec 20 mg, amoxicillin 1 g and clarithromycin 500 mg are all administered two times daily for one week.' The SPC adds that the choice of combination should follow 'official national, regional and local guidance regarding bacterial resistance, duration of treatment (most commonly 7 days but sometimes up to 14 days), and appropriate use of antibacterial agents.' || NO DOSING BELOW 1 YEAR OF AGE OR BELOW 10 kg appears anywhere in this SPC, and none is published here. || ADMINISTRATION (section 4.2 verbatim): 'Patients can open the capsule and swallow the contents with half a glass of water or after mixing the contents in a slightly acidic fluid e.g. fruit juice or applesauce, or in non-carbonated water... the dispersion should be taken immediately (or within 30 minutes) and always be stirred just before drinking and rinsed down with half a glass of water. Alternatively, patients can suck the capsule and swallow the pellets with half a glass of water. The enteric-coated pellets must not be chewed.' || Verify all paediatric dosing against a children's formulary before prescribing.

Dose adjustments

Renal

Section 4.2 verbatim: 'Renal impairment - Dose adjustment is not needed in patients with impaired renal function (see section 5.2).' Section 4.8 separately lists 'Rare: Tubulointerstitial nephritis (with possible progression to renal failure)' as an adverse reaction.

Hepatic

Section 4.2 verbatim: 'Hepatic impairment - In patients with impaired hepatic function a daily dose of 10 mg to 20 mg may be sufficient (see section 5.2).' Section 4.8 additionally records 'Very rare: Hepatic failure, encephalopathy in patients with pre-existing liver disease.'

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Section 4.3 verbatim: 'Hypersensitivity to the active substance, substituted benzimidazoles or to any of the excipients listed in section 6.1.'
  • Section 4.3 verbatim: 'Omeprazole like other proton pump inhibitors (PPIs) must not be used concomitantly with nelfinavir (see section 4.5).'
  • Not a contraindication but a not-recommended combination with a dose ceiling attached (section 4.4): 'Co-administration of atazanavir with proton pump inhibitors is not recommended... If the combination of atazanavir with a proton pump inhibitor is judged unavoidable, close clinical monitoring (e.g. virus load) is recommended in combination with an increase in the dose of atazanavir to 400 mg with 100 mg of ritonavir; omeprazole 20 mg should not be exceeded.'
  • Not a contraindication but a diagnostic bar (section 4.4): 'In the presence of any alarm symptom (e.g. significant unintentional weight loss, recurrent vomiting, dysphagia, haematemesis or melena) and when gastric ulcer is suspected or present, malignancy should be excluded, as treatment may alleviate symptoms and delay diagnosis.'
  • Not a contraindication but a discouraged combination (section 4.4): 'An interaction is observed between clopidogrel and omeprazole... The clinical relevance of this interaction is uncertain. As a precaution, concomitant use of omeprazole and clopidogrel should be discouraged.'

Side effects

  • Most common, 1 to 10% of patients (section 4.8): headache, abdominal pain, constipation, diarrhoea, flatulence and nausea/vomiting.
  • Common gastrointestinal (section 4.8): abdominal pain, constipation, diarrhoea, flatulence, nausea/vomiting, benign fundic gland polyps.
  • Common nervous system (section 4.8): headache. Uncommon: dizziness, paraesthesia, somnolence. Rare: taste disturbance.
  • Severe cutaneous adverse reactions (section 4.4 and 4.8): Stevens-Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms (DRESS) and acute generalized exanthematous pustulosis (AGEP), 'which can be life-threatening or fatal, have been reported very rarely and rarely'.
  • Blood and lymphatic (section 4.8): rare leukopenia and thrombocytopenia; very rare agranulocytosis and pancytopenia.
  • Immune system (section 4.8): rare hypersensitivity reactions, e.g. fever, angioedema and anaphylactic reaction/shock.
  • Metabolism (section 4.8): rare hyponatraemia; frequency not known hypomagnesaemia - 'severe hypomagnesaemia may result in hypocalcaemia. Hypomagnesaemia may also be associated with hypokalaemia.'
  • Psychiatric (section 4.8): uncommon insomnia; rare agitation, confusion, depression; very rare aggression, hallucinations.
  • Hepatobiliary (section 4.8): uncommon increased liver enzymes; rare hepatitis with or without jaundice; very rare hepatic failure and encephalopathy in patients with pre-existing liver disease.
  • Skin (section 4.8): uncommon dermatitis, pruritus, rash, urticaria; rare alopecia, photosensitivity, AGEP, DRESS; very rare erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis; not known subacute cutaneous lupus erythematosus.
  • Musculoskeletal (section 4.8): uncommon fracture of the hip, wrist or spine; rare arthralgia, myalgia; very rare muscular weakness.
  • Renal (section 4.8): rare tubulointerstitial nephritis, with possible progression to renal failure.
  • Other (section 4.8): uncommon vertigo; rare bronchospasm, blurred vision, dry mouth, stomatitis, gastrointestinal candidiasis; not known microscopic colitis.
  • Fracture risk (section 4.4): proton pump inhibitors 'especially if used in high doses and over long durations (> 1 year), may modestly increase the risk of hip, wrist and spine fracture'.
  • Reduced vitamin B12 absorption on long-term therapy, due to hypo- or achlorhydria (section 4.4).

Monitoring

  • Magnesium (section 4.4 verbatim): 'For patients expected to be on prolonged treatment or who take PPIs with digoxin or drugs that may cause hypomagnesaemia (e.g. diuretics), healthcare professionals should consider measuring magnesium levels before starting PPI treatment and periodically during treatment.'
  • Vitamin B12 status on long-term therapy (section 4.4): reduced absorption 'should be considered in patients with reduced body stores or risk factors for reduced vitamin B 12 absorption on long-term therapy'.
  • Paediatric symptom review (section 4.2): 'If symptom control has not been achieved after 2 to 4 weeks the patient should be investigated further.'
  • Adult symptom review (section 4.2): 'If symptom control has not been achieved after four weeks treatment with Losec 20 mg daily, further investigation is recommended.'
  • Exclude malignancy where alarm symptoms are present or gastric ulcer is suspected, before attributing symptoms to reflux (section 4.4).
  • Skin - severe cutaneous adverse reactions including Stevens-Johnson syndrome, toxic epidermal necrolysis, DRESS and AGEP have been reported (sections 4.4 and 4.8).
  • Bone health in patients at risk of osteoporosis on high-dose, long-duration therapy (section 4.4): 'Patients at risk of osteoporosis should receive care according to current clinical guidelines.'
  • CYP2C19-metabolised drugs when starting or stopping omeprazole (section 4.4): 'Omeprazole is a CYP2C19 inhibitor. When starting or ending treatment with omeprazole, the potential for interactions with drugs metabolised through CYP2C19 should be considered.'
  • Ongoing indication - this SPC sets a defined treatment time for each paediatric indication rather than open-ended therapy (section 4.2).

Clinical monograph

How it works

It irreversibly inhibits the gastric H+/K+-ATPase (proton pump) in parietal cells, markedly reducing gastric acid secretion.

Prescribing in practice

  • The most important paediatric point is that PPIs should be used for a defined indication and reviewed regularly rather than continued indefinitely, as reflux is often physiological in infants and prolonged acid suppression is associated with increased gastrointestinal and respiratory infections.
  • It may mask symptoms of more serious upper-gastrointestinal disease and can interact with drugs requiring gastric acidity for absorption or metabolised via CYP enzymes.
  • It is given once daily before food, with dispersible formulations available; doses are weight-based and should be confirmed against a children's formulary.

Monitoring

Monitor symptom response and the continued need for treatment at review, with attention to growth and any alarm features.

Counselling the patient

  • Give before a meal, and disperse the tablet or use granules as directed for young children.
  • The aim is to use the lowest effective course, with regular review of whether it is still needed.
  • Report persistent vomiting, poor feeding, weight loss or blood in vomit or stool.

Evidence & guidelines

NICE guidance on gastro-oesophageal reflux in children supports time-limited PPI use for reflux oesophagitis and recommends regular review.

Reference: NICE NG1 GORD; ESPGHAN GORD Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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