What is the recommended dose of omeprazole (Proton Pump Inhibitor) intravenous (IV) for children?

Intravenous Omeprazole Dosing in Children

For children requiring IV omeprazole, administer 40 mg/1.73 m² once daily as a 1-hour infusion, as this is the only dose demonstrated to effectively maintain gastric pH >4 for >90% of the time in infants and young children. 1

Evidence-Based Dosing Recommendations

Standard IV Dosing

• The dose of 20 mg/1.73 m² IV once daily is inadequate and fails to maintain therapeutic gastric pH control (median pH 3.35, with only 44.8% of time at pH >4) 1
• The effective dose is 40 mg/1.73 m² IV once daily, which achieves median gastric pH of 6.99 and maintains pH >4 for 90.6% of monitored time 1
• Administer as a 1-hour infusion once daily at a consistent time (typically 8 AM) 1

Pharmacokinetic Considerations

• Plasma concentration curves demonstrate rapid elimination in infants and young children (ages 4.5-27 months) 1
• The area under the curve (AUC) at 40 mg/1.73 m² is 3.95 μg·mL⁻¹·h⁻¹ (range 1.9-4.9), significantly higher than the inadequate 20 mg/1.73 m² dose 1
• Systemic clearance is similar between dose groups (median 0.42-0.68 L·kg⁻¹·h⁻¹), indicating dose-dependent efficacy rather than altered metabolism 1

Critical Clinical Pitfalls

Common Dosing Errors to Avoid

• Do not extrapolate adult dosing to pediatric patients, as children have different pharmacokinetics 1
• Do not use 20 mg/1.73 m² as the starting dose for IV therapy—this consistently fails to achieve therapeutic effect 1
• Do not assume oral dosing equivalence—IV dosing requirements differ from oral formulations due to bioavailability differences 1, 2

When IV Route is Indicated

• IV omeprazole should be reserved for critical situations where oral administration is not feasible 1
• Consider IV route for children who are NPO, have severe vomiting, or require immediate gastric acid suppression 1

Transition to Oral Therapy

Oral Dosing After IV Stabilization

• Once oral intake is tolerated, transition to oral omeprazole at 0.7 mg/kg/day as initial dose (divided into 2 doses) 2, 3
• Approximately 50% of infants require dose escalation beyond 0.7 mg/kg/day for adequate control 2
• Maximum doses up to 2.8 mg/kg/day may be necessary in refractory cases 2

For Eosinophilic Esophagitis (Different Indication)

• If treating eosinophilic esophagitis specifically, use 1 mg/kg twice daily (maximum 40 mg twice daily) for 8-12 weeks 4, 5
• This higher dosing regimen (equivalent to omeprazole 20 mg twice daily) demonstrates superior response rates (50.8%) compared to standard doses (35.8%) 4

Safety Monitoring

Short-Term Safety Profile

• IV omeprazole has been administered to children aged 4.5-27 months without serious complications or side effects 1
• Oral omeprazole has been used safely for periods of 5.5-26 months in children with severe esophagitis 3

Long-Term Considerations

• Monitor for elevated transaminases (reported in 7 of 15 patients in one series) 3
• Monitor fasting gastrin levels, which may elevate 3-5.5 times the upper limit of normal 3
• Long-term use (>2.5 years) may be associated with enterochromaffin cell hyperplasia in up to 50% of children 5

Body Surface Area Calculation

To calculate 40 mg/1.73 m² for a specific patient:

• Use the Mosteller formula: BSA (m²) = √[(height in cm × weight in kg)/3600]
• Multiply patient's BSA by 40 mg/1.73 m² to determine the dose
• For example, a 10 kg infant with BSA of 0.5 m² would receive: (0.5/1.73) × 40 mg = 11.6 mg IV once daily