Ranitidine Dosing in Pediatric Patients
Recommended Dosing by Indication
For GERD and erosive esophagitis in children aged 1 month to 16 years, administer ranitidine at 5-10 mg/kg/day divided into 2-3 doses, with a maximum daily dose of 300 mg. 1, 2
Standard Oral Dosing for GERD/Peptic Ulcer Disease
- Treatment of active duodenal and gastric ulcers: 2-4 mg/kg twice daily (maximum 300 mg/day) 2
- Maintenance of healing: 2-4 mg/kg once daily (maximum 150 mg/day) 2
- GERD and erosive esophagitis: 5-10 mg/kg/day divided into 2 doses 1, 2
The FDA-approved age range is 1 month to 16 years, with weight-based dosing as outlined above. 1 There is insufficient pharmacokinetic data for neonates less than 1 month of age to make dosing recommendations. 2
Critical Care and Stress Ulcer Prophylaxis
For critically ill children requiring stress ulcer prophylaxis, a minimum of 3 mg/kg/day intravenously is necessary to maintain gastric pH >4. 3
- The commonly cited dose of 2-4 mg/kg/day results in poor gastric pH control in 36% of critically ill children 3
- Children receiving <3 mg/kg/day had poor pH control in 71% of cases, compared to only 19% with doses ≥3 mg/kg/day 3
- Optimal IV dosing for AGMD prophylaxis: 1.5 mg/kg IV every 6 hours (6 mg/kg/day total) 4
- This higher dosing achieved pH ≥4 for >80% of the study period in 80% of patients 4
Age-Specific Considerations for Neonates
Preterm infants require significantly lower doses than term neonates due to prolonged drug effect and delayed time to peak pH. 5
- Preterm infants (<37 weeks): 0.5 mg/kg twice daily (1 mg/kg/day total) 5
- Term neonates: 1.5 mg/kg three times daily (4.5 mg/kg/day total) 5
- The effect of a single dose lasts longer in preterm versus term infants, and time to maximum gastric pH is significantly prolonged in preterm infants 5
Anaphylaxis Management (Adjunctive Therapy)
For anaphylaxis, ranitidine is second-line adjunctive therapy and should never be administered alone without epinephrine. 1, 6, 7
- Pediatric IM/IV dose: 1 mg/kg per dose (maximum 50 mg) 1, 6
- Dosing range: 12.5-50 mg based on weight 6, 7
- IV administration: Dilute in 20 mL D5W and administer over 5 minutes 1, 7
- The combination of diphenhydramine plus ranitidine is superior to diphenhydramine alone 1, 6
Formulation and Administration
Ranitidine effervescent tablets have significantly better taste acceptance than syrup in children. 1, 8
- 71% of children aged 4-8 years preferred the citrus-flavored effervescent formulation over peppermint-flavored syrup 8
- Effervescent tablets are available as 25 mg dissolved in 5 mL water 8
- Better taste acceptance may improve compliance in pediatric patients 1, 8
Important Clinical Caveats
Ranitidine develops tachyphylaxis within 6 weeks of continuous use and requires 2-3 times daily dosing due to its 6-hour acid suppression duration. 1
- Doses ≥3 mg/kg/dose are required for acid suppression lasting beyond 6 hours 9
- During the last 2 hours of a 6-hour dosing interval, low doses (<3 mg/kg) maintained pH >4 only 29% of the time versus 89% with high doses (≥3 mg/kg) 9
- Ranitidine is less effective than PPIs for healing erosive esophagitis 1
Renal Impairment Adjustment
For patients with creatinine clearance <50 mL/min, reduce dosing to 150 mg every 24 hours, with cautious increases to every 12 hours if clinically required. 2
- Hemodialysis reduces circulating ranitidine levels; time scheduled doses to coincide with the end of hemodialysis 2