Ranitidine Dosing in Pediatric Patients
For pediatric patients aged 1 month to 16 years with GERD or peptic ulcer disease, the recommended oral dose of ranitidine is 5-10 mg/kg/day divided into 2-3 doses, with a maximum of 300 mg/day. 1, 2
Standard Oral Dosing by Indication
GERD and Erosive Esophagitis
- Administer 5-10 mg/kg/day divided into 2 doses for treatment of GERD and erosive esophagitis 1, 2
- The FDA label supports this dosing range based on published literature and pharmacokinetic data in pediatric patients 2
- This is the most commonly used indication requiring the higher end of the dosing spectrum 1
Duodenal and Gastric Ulcers
- Treatment phase: 2-4 mg/kg twice daily (maximum 300 mg/day) 2
- Maintenance phase: 2-4 mg/kg once daily (maximum 150 mg/day) 2
- These recommendations are derived from adult clinical studies and pediatric pharmacokinetic data 2
Formulation Considerations
- Ranitidine effervescent tablets (dissolved in water) are preferred over syrup based on taste acceptance studies 1, 3
- 71% of children aged 4-8 years preferred the effervescent formulation over peppermint-flavored syrup 3
- Better taste acceptance facilitates compliance in pediatric patients 3
Intramuscular Dosing for Anaphylaxis
- IM dose: 1 mg/kg per dose, maximum 50 mg 1, 4
- Used as second-line therapy in combination with diphenhydramine; never administer H2 antagonists alone in anaphylaxis 4
- Epinephrine remains the first-line treatment 4
Critical Care Dosing Adjustments
Important caveat: Standard dosing recommendations may be insufficient in critically ill children. Research evidence demonstrates:
- Critically ill children require higher doses: A minimum of 3 mg/kg/day IV is needed to maintain gastric pH >4 5
- 71% of patients receiving <3 mg/kg/day had poor gastric pH control compared to only 19% receiving ≥3 mg/kg/day 5
- For stress ulcer prophylaxis in ICU patients: 1.5 mg/kg IV every 6 hours (6 mg/kg/day total) was most effective 6
- Both bolus dosing and continuous infusion at 4 mg/kg/day are effective at maintaining gastric pH >4 7
Neonatal Dosing (Special Population)
Preterm vs. term neonates require different dosing strategies:
- Preterm infants (<37 weeks): 0.5 mg/kg twice daily 8
- Term neonates: 1.5 mg/kg three times daily 8
- Preterm infants have prolonged drug effect and require significantly smaller doses than term infants 8
- There is insufficient data for neonates <1 month of age to make formal FDA recommendations 2
Renal Impairment Adjustments
- For creatinine clearance <50 mL/min: 150 mg every 24 hours 2
- May increase frequency to every 12 hours if clinically required, with caution 2
- Time dosing to coincide with end of hemodialysis when applicable 2
Important Clinical Pitfalls
Tachyphylaxis develops within 6 weeks of continuous use, limiting long-term effectiveness 1
Ranitidine is less effective than PPIs for healing erosive esophagitis and requires 2-3 times daily dosing due to only 6 hours of acid suppression 1
Do not underdose in critically ill children: The commonly cited 2-4 mg/kg/day range results in poor gastric pH control in 36% of ICU patients 5