Famotidine Dosing for a 31-kg Child
No, 2 mL twice daily of famotidine suspension (40 mg/5 mL) is insufficient for a 31-kg child—this provides only 16 mg twice daily (32 mg/day total), which is below the recommended dose of 0.5 mg/kg twice daily (approximately 15.5 mg per dose, or 31 mg/day total). While the volume is close to appropriate, you should verify the exact dose needed and adjust accordingly.
Recommended Dosing
For a 31-kg child, the appropriate famotidine dose is 0.5 mg/kg twice daily, which equals approximately 15.5 mg per dose or 31 mg total daily. 1, 2
- Using the 40 mg/5 mL suspension (8 mg/mL concentration), 2 mL provides 16 mg per dose 3
- This gives 32 mg/day total, which is slightly above but acceptably close to the target of 31 mg/day 2
- The 2 mL BID dosing is therefore clinically appropriate and represents standard pediatric dosing 1, 2
Dosing Algorithm for Children
For children over 1 year of age, use 0.5 mg/kg per dose every 8-12 hours (typically twice daily): 1, 4
- Children >1 year: 0.5 mg/kg/dose every 12 hours 1, 4
- Maximum single dose: 20 mg 3
- Maximum daily dose: 40 mg 3
For infants <3 months: Use 0.5 mg/kg once daily due to immature renal function 4
For infants 3-12 months: Use 0.5 mg/kg every 12 hours 4
Clinical Efficacy Considerations
This dosing regimen (0.5 mg/kg BID) has demonstrated effectiveness in pediatric studies: 2
- Heals gastroduodenal ulcers within 8 weeks in children 2
- Maintains intragastric pH >4.0 for approximately 9 hours per dose 5
- Oral bioavailability is approximately 50% in children, similar to adults 2
Important caveat: Prolonged IV use may lead to tachyphylaxis, with decreased duration of acid suppression after repeated doses 5
Administration Instructions
- May be given with or without food 3
- Can be administered with antacids if needed 3
- For twice-daily dosing, give in morning and before bedtime 3
Monitoring and Safety
Famotidine is generally well-tolerated in children with minimal side effects: 2, 6