Omeprazole Dosing for 6-Month-Old Pediatric Patient
For a 6-month-old infant with severe or refractory GERD, start omeprazole at 0.7 mg/kg/day divided into two doses, which can be escalated up to 1.4-2.8 mg/kg/day in divided doses based on clinical response. 1
Weight-Based Dosing Algorithm
- Initial dose: 0.7 mg/kg/day divided into 2 doses (e.g., for a 7 kg infant: approximately 2.5 mg twice daily) 1, 2
- Dose escalation: If inadequate response after 14 days, increase in increments of 0.7 mg/kg/day 2
- Maximum dose: Up to 2.8 mg/kg/day may be required in refractory cases 1, 2
The majority of infants under 2 years respond to the initial 0.7 mg/kg/day dosage, though approximately 40% may require higher doses up to 1.4 mg/kg/day, and occasionally up to 2.8 mg/kg/day for adequate acid suppression 2.
Preparation and Administration
Since no commercial pediatric formulation exists for this age group, prepare a compounded suspension:
- Use omeprazole capsules mixed with applesauce for immediate administration, OR 1
- Have a retail pharmacy compound a 6 mg/mL suspension 1
- For a typical 7 kg infant at 0.7 mg/kg/day (approximately 5 mg/day): Administer 0.83 mL of 6 mg/mL suspension divided into two doses (approximately 0.4 mL twice daily) 1
The compounded suspension maintains stability and allows accurate dosing for small infants who cannot swallow capsules 1.
Clinical Monitoring
- Assess response at 14 days: If symptoms persist or pH monitoring shows inadequate acid suppression, escalate the dose 2
- Monitor for adverse effects: Headaches, diarrhea, and nausea are most common, though generally well-tolerated in this age group 1
- Long-term considerations: For therapy exceeding 2.5 years, monitor for enterochromaffin cell hyperplasia, though this is rarely relevant for initial treatment courses 1
Critical Dosing Considerations
Common pitfall: Underdosing is frequent in infants under 2 years because providers often use the older pediatric dosing (10-20 mg once daily for children ≥2 years), which is inadequate for this age group 1. Infants require weight-based dosing starting at 0.7 mg/kg/day, not fixed-dose regimens 1, 2.
Pharmacokinetic differences: Infants have prolonged elimination half-lives (55-90 hours vs. 30 hours in adults) and altered volumes of distribution, necessitating the weight-based approach rather than extrapolating adult doses 3, 4.
Dose titration is essential: Unlike older children where fixed doses are standard, infants frequently require individualized dose escalation based on clinical response and pH monitoring when available 2. Approximately 50% of infants need doses higher than the initial 0.7 mg/kg/day to achieve adequate acid control 2.