Maximum Pediatric Dose of Amoxicillin
The maximum pediatric dose of amoxicillin is 90 mg/kg/day for most infections, with each individual dose not to exceed 500 mg, though this can vary by specific indication. 1, 2
Dosing Guidelines by Age and Weight
Children ≥ 3 months and < 40 kg:
Mild/Moderate Infections:
- 25 mg/kg/day divided every 12 hours OR
- 20 mg/kg/day divided every 8 hours 1
Severe Infections:
- 45 mg/kg/day divided every 12 hours OR
- 40 mg/kg/day divided every 8 hours 1
Lower Respiratory Tract Infections:
- 45 mg/kg/day divided every 12 hours OR
- 40 mg/kg/day divided every 8 hours 1
Children < 12 weeks (3 months):
- Maximum of 30 mg/kg/day divided every 12 hours due to incompletely developed renal function 1
Special Indications with Higher Dosing
Group A Streptococcal Pharyngitis:
- 50 mg/kg/day in 2 doses (maximum = 1,000 mg per dose) 2
Community-Acquired Pneumonia:
- Outpatient treatment: 90 mg/kg/day in 2 doses (maximum = 4,000 mg/day) 2
Anthrax Post-Exposure Prophylaxis:
- Standard dose: 45 mg/kg/day divided into 3 daily doses given every 8 hours; each dose should not exceed 500 mg 2
- American Academy of Pediatrics recommendation for anthrax: 80 mg/kg/day divided into 3 daily doses; each dose should not exceed 500 mg 2
Important Considerations
Dosing Frequency
- Twice-daily dosing (every 12 hours) is as effective as three-times-daily dosing for most infections and may improve compliance 3, 4
Duration of Treatment
- For Streptococcus pyogenes infections: minimum 10 days to prevent acute rheumatic fever 1
- For most infections: continue for 48-72 hours after patient becomes asymptomatic 1
Weight-Based vs. Age-Based Dosing
- Weight-based dosing is preferred over age-based dosing for accuracy 5
Maximum Daily Dose Considerations
- For children with higher weight, particularly those with obesity, the calculated dose may exceed the standard adult dose of 1,500 mg/day 6
- When calculated dose exceeds adult dosing, clinical judgment is required, with many providers capping at adult dosing 6
Renal Impairment Adjustments
For children with severe renal impairment:
- GFR 10-30 mL/min: 500 mg or 250 mg every 12 hours
- GFR <10 mL/min: 500 mg or 250 mg every 24 hours 1
Administration Guidance
- Administer at the start of a meal to minimize gastrointestinal intolerance 1
- For oral suspension, shake well before using 1
Remember that while 90 mg/kg/day is generally considered the maximum for most indications, the specific maximum dose should be tailored to the severity and type of infection being treated, with careful attention to the individual dose limit of 500 mg per dose for most pediatric patients.