Maximum Amoxicillin Dose for a 62.5 lb Pediatric Patient
For a pediatric patient weighing 62.5 lbs (28.4 kg), the maximum daily dose of amoxicillin is 2,556 mg/day (90 mg/kg/day), which should not exceed the adult maximum of 4,000 mg/day. 1, 2
Weight-Based Dosing Calculation
- Patient weight: 62.5 lbs = 28.4 kg
- Maximum pediatric dose: 90 mg/kg/day for severe infections or high pneumococcal resistance areas 1, 2
- Calculated maximum: 28.4 kg × 90 mg/kg = 2,556 mg/day
- Absolute maximum: The FDA label specifies that the adult maximum of 4,000 mg/day applies to pediatric patients weighing ≥40 kg, but this child is under that threshold 2
Dosing by Indication
For Mild to Moderate Respiratory Infections
- Standard dose: 45 mg/kg/day divided every 12 hours 1, 2
- For this patient: 28.4 kg × 45 mg/kg = 1,278 mg/day (639 mg twice daily)
For Severe Infections or High Resistance Areas
- High dose: 90 mg/kg/day divided every 12 hours 1, 2
- For this patient: 28.4 kg × 90 mg/kg = 2,556 mg/day (1,278 mg twice daily)
- This higher dosing is specifically recommended by the Infectious Diseases Society of America for community-acquired pneumonia in areas with high pneumococcal resistance 1
For Group A Streptococcal Infections
- Recommended dose: 50-75 mg/kg/day in 2 doses 1
- For this patient: 1,420-2,130 mg/day (710-1,065 mg twice daily)
- Maximum per dose: Should not exceed 1,000 mg per dose 1
Critical Dosing Considerations
The FDA label clearly states that for pediatric patients weighing less than 40 kg, dosing should follow weight-based calculations rather than adult fixed doses. 2 Since this patient weighs 28.4 kg, the 90 mg/kg/day maximum (2,556 mg/day) applies, not the adult 4,000 mg/day maximum.
Common Pitfall to Avoid
- Do not use adult fixed doses (500 mg or 875 mg tablets) for children under 40 kg 2
- Always calculate based on actual body weight using mg/kg dosing 2
- The 875 mg tablet formulation is specifically NOT recommended for patients with severe renal impairment, but this is a separate consideration from weight-based dosing 2
Administration Guidelines
- Timing: Administer at the start of meals to minimize gastrointestinal intolerance 2
- Duration: Minimum 48-72 hours beyond symptom resolution; 10 days for Streptococcus pyogenes infections 2
- Monitoring: Children should show clinical improvement within 48-72 hours; if not, reevaluation is necessary 1
Evidence Quality Note
Recent high-quality research (2021) demonstrated that both lower (35-50 mg/kg/day) and higher (70-90 mg/kg/day) doses of amoxicillin showed similar efficacy for uncomplicated community-acquired pneumonia, with comparable adverse events and antimicrobial resistance patterns 3. However, the higher dose remains recommended for severe infections and high-resistance areas per current guidelines 1.