What is the maximum recommended daily dose of amoxicillin (amox) for a 6-year-old child?

Maximum Amoxicillin Dose for a 6-Year-Old Child

The maximum recommended daily dose of amoxicillin for a 6-year-old child is 90 mg/kg/day divided into 2 doses, with an absolute maximum limit of 4000 mg/day regardless of weight. 1, 2

Standard Dosing Framework

For most common pediatric infections in a 6-year-old child, the dosing strategy depends on infection severity and suspected pathogens:

Mild to Moderate Infections

• Standard dose: 45 mg/kg/day divided into 2 doses (or 40 mg/kg/day divided into 3 doses) for uncomplicated infections such as mild otitis media, pharyngitis, or skin infections 2
• This provides adequate coverage for penicillin-susceptible Streptococcus pneumoniae and other common pathogens 3

Severe Infections or Resistant Pathogens

• High dose: 90 mg/kg/day divided into 2 doses for severe infections, pneumonia, recurrent otitis media, or when resistant S. pneumoniae is suspected 1, 2
• The Infectious Diseases Society of America specifically recommends this high-dose regimen for community-acquired pneumonia in children 3, 1
• This dosing achieves adequate drug levels to overcome intermediate penicillin resistance (MIC ≤2.0 μg/mL) 3

Absolute Maximum Dose

The FDA-mandated absolute maximum is 4000 mg/day (4 grams/day), regardless of the child's weight. 4, 2

• For a typical 6-year-old weighing 20-25 kg, the calculated dose of 90 mg/kg/day would be 1800-2250 mg/day, well below the absolute maximum 1
• Children weighing >44 kg would reach the 4000 mg/day cap before reaching 90 mg/kg/day 4

Clinical Application for a 6-Year-Old

For practical dosing in a 6-year-old child:

• If the child weighs 20 kg: Maximum dose = 1800 mg/day (900 mg twice daily) 1
• If the child weighs 25 kg: Maximum dose = 2250 mg/day (1125 mg twice daily) 1
• If the child weighs 30 kg: Maximum dose = 2700 mg/day (1350 mg twice daily) 1

Important Clinical Considerations

Twice-Daily vs Three-Times-Daily Dosing

• Twice-daily dosing is preferred for improved compliance and similar efficacy, particularly at the 90 mg/kg/day dose 1, 2
• The high-dose twice-daily regimen maintains adequate time above MIC for resistant organisms 5, 6

Duration of Therapy

• Continue treatment for minimum 48-72 hours beyond symptom resolution 2
• For Streptococcus pyogenes infections, treat for at least 10 days to prevent acute rheumatic fever 2

Common Pitfalls to Avoid

• Do not use the 875 mg tablet formulation in children with renal impairment (GFR <30 mL/min), as this exceeds safe dosing 2
• Always calculate dose based on actual body weight, not age alone, to avoid underdosing or overdosing 7
• Prescriptions should clearly state: total daily dose, number of divided doses, duration, indication, and child's weight to prevent pharmacy dispensing errors 7

Renal Impairment Adjustments

• For children with GFR 10-30 mL/min: Maximum 500 mg every 12 hours 2
• For children with GFR <10 mL/min: Maximum 500 mg every 24 hours 2

Evidence Quality Note

The 90 mg/kg/day high-dose recommendation is supported by multiple high-quality guidelines including the Infectious Diseases Society of America and the American Academy of Pediatrics, specifically addressing the emergence of penicillin-resistant S. pneumoniae 3, 1. Research demonstrates that lower doses (40 mg/kg/day) are inadequate for resistant organisms, particularly during viral coinfection 5.