Pediatric Ranitidine Dosing Recommendations
The recommended pediatric dose of ranitidine is 2-4 mg/kg/day divided into 2-3 doses for most indications, with a minimum of 3 mg/kg/day needed for effective gastric pH control in critically ill children. 1, 2
Age-Specific Dosing
Neonates and Infants
Children (1 month to 16 years)
- General dosing: 2-4 mg/kg/day divided into 2 doses (maximum 300 mg/day) 1
- For GERD and erosive esophagitis: 5-10 mg/kg/day divided into 2 doses 1
- For critically ill children: Minimum 3 mg/kg/day is recommended as lower doses often result in poor gastric pH control 2
- For acute gastric mucosal damage prophylaxis: 1.5 mg/kg IV every 6 hours (6 mg/kg/day) 4
Children by Weight
Indication-Specific Dosing
Duodenal and Gastric Ulcers
- Treatment: 2-4 mg/kg twice daily (maximum 300 mg/day) 1
- Maintenance: 2-4 mg/kg once daily (maximum 150 mg/day) 1
GERD and Erosive Esophagitis
- Treatment: 5-10 mg/kg/day divided into 2 doses 1
Anaphylaxis (as adjunctive therapy)
- Dose: 1 mg/kg (range 12.5-50 mg) IV 5
- Administration: Dilute in 5% dextrose to a total volume of 20 mL and inject intravenously over 5 minutes 5
- Note: H2 antihistamines are second-line therapy to epinephrine and should never be administered alone in anaphylaxis treatment 5
Clinical Pearls and Caveats
- Dosing frequency matters: The effect of ranitidine lasts longer in preterm infants than in term infants 3
- pH control threshold: For effective acid suppression, gastric pH should be maintained above 4 2, 3, 6
- Dose-dependent effect: Higher doses (≥3 mg/kg/dose) maintain gastric pH >4 for longer periods compared to lower doses (<3 mg/kg/dose) 6
- Formulation preference: In taste preference studies, children prefer the effervescent tablet formulation over the syrup, which may improve compliance 7
Special Populations
Renal Impairment
- For patients with creatinine clearance <50 mL/min, reduce dose to 150 mg every 24 hours 1
- Frequency may be increased to every 12 hours with caution if clinically necessary 1
- For hemodialysis patients, schedule dosing to coincide with the end of hemodialysis 1
Monitoring
- In critically ill children, monitor gastric pH to ensure it remains >4 2
- If pH control is inadequate, consider increasing the dose to at least 3 mg/kg/day 2, 6
This evidence-based dosing guidance ensures optimal therapeutic effect while minimizing the risk of adverse events in pediatric patients requiring ranitidine therapy.