What is the recommended dose of omeprazole (omeprazole) for upper gastrointestinal bleeding (UGIB) in a 6-month-old infant?

Omeprazole for Upper Gastrointestinal Bleeding in a 6-Month-Old Infant

For a 6-month-old infant with upper gastrointestinal bleeding, omeprazole should be administered intravenously at a dose of 40 mg/1.73 m² once daily, as this is the only pediatric dosing regimen proven effective in maintaining gastric pH >4 in infants under 30 months of age. 1

Critical Context: Pediatric vs. Adult Dosing

The standard adult high-dose protocol (80 mg IV bolus followed by 8 mg/hour continuous infusion for 72 hours) used for non-variceal upper GI bleeding 2 has not been studied or validated in infants. The pharmacokinetics and dosing requirements differ substantially in this age group 1.

Evidence-Based Pediatric Dosing

Intravenous Administration

• The dose of 40 mg/1.73 m² once daily as a 1-hour infusion is required to maintain gastric pH >4 for more than 90% of the time in infants aged 4.5 to 27 months 1
• A lower dose of 20 mg/1.73 m² is inadequate, achieving pH >4 for only 44.8% of the time (median pH 3.35) compared to 90.6% with the higher dose (median pH 6.99) 1
• For a typical 6-month-old infant weighing approximately 7-8 kg with body surface area of ~0.4 m², this translates to approximately 16 mg once daily 1

Oral Administration (if appropriate)

• For less severe gastroesophageal reflux disease in infants, oral omeprazole at 0.7-1.05 mg/kg/day in 2 divided doses is effective for the majority of children under 2 years 3
• Some infants may require doses up to 2.8 mg/kg/day 3
• However, oral dosing is not appropriate for acute upper GI bleeding requiring immediate acid suppression 2

Dosing Frequency Considerations

• Standard once-daily dosing at 0.5 mg/kg every 12 hours may show discontinuous effect in some pediatric transplant patients, with acid suppression dissipating before the next dose 4
• If gastric pH monitoring reveals inadequate acid suppression, shortening the dosing interval to every 6-8 hours increases mean pH from 3.9 to 6.6 4
• Monitor clinical response and consider more frequent dosing if bleeding persists 4

Critical Caveats for Infants

Endoscopic Intervention Remains Primary

• PPI therapy must complement, not replace, endoscopic evaluation and hemostasis 2
• Start PPI therapy as soon as possible, even before endoscopy, but do not delay urgent endoscopic intervention 2, 5

Preparation and Administration

• Omeprazole should be suspended in sodium bicarbonate for nasogastric administration if oral route is used 4
• IV formulation should be given as a 1-hour infusion, not as a bolus in this age group 1

Duration of Therapy

• After initial IV therapy and successful hemostasis, transition to oral PPI therapy 2
• Continue oral therapy for 6-8 weeks to allow complete mucosal healing 2, 5
• Do not discontinue therapy prematurely, as this prevents adequate mucosal healing 5

Common Pitfalls to Avoid

• Do not use adult high-dose continuous infusion protocols in infants - these have not been validated and pharmacokinetics differ significantly 1
• Do not use 20 mg/1.73 m² dosing - this is inadequate for maintaining therapeutic gastric pH in infants 1
• Do not rely solely on PPI therapy without addressing the underlying cause and ensuring appropriate endoscopic evaluation 2, 5
• Do not forget to test for H. pylori if peptic ulcer disease is identified, though this is less common in infants 5

Special Monitoring

• Consider gastric pH monitoring if available to ensure adequate acid suppression, particularly if bleeding persists 1
• Watch for signs of inadequate response that may require dosing interval adjustment to every 6-8 hours 4
• No serious complications or side effects were reported in pediatric studies at these doses 3, 4, 1