What is the maximum daily dose of amoxicillin for a 2‑year‑old child?

Maximum Daily Dose of Amoxicillin for a 2-Year-Old Child

The maximum daily dose of amoxicillin for a 2-year-old child is 90 mg/kg/day (not to exceed 4,000 mg/day total), divided into two doses given every 12 hours. 1

Standard Dosing Framework

The appropriate amoxicillin dose for a 2-year-old depends on the infection severity and local resistance patterns:

Mild to Moderate Infections

• 45 mg/kg/day divided into 2 doses (every 12 hours) is recommended for uncomplicated respiratory tract infections, skin infections, and genitourinary infections 1
• This provides adequate coverage for most susceptible pathogens including Streptococcus pneumoniae, Haemophilus influenzae (non-β-lactamase producing), and Streptococcus pyogenes 1

Severe Infections or High-Resistance Areas

• 90 mg/kg/day divided into 2 doses (every 12 hours) is the maximum recommended dose for severe infections or areas with high pneumococcal resistance 1, 2
• This high-dose regimen is specifically indicated for:
  • Community-acquired pneumonia in children <2 years old 1
  • Areas with >10% penicillin-resistant S. pneumoniae 1
  • Recent antibiotic exposure within the past 30 days 1
  • Children attending daycare 1
  • Severe infections requiring hospitalization 1

Absolute Maximum Dose

Regardless of weight, the total daily dose should never exceed 4,000 mg (4 grams) per day 1, 2

Practical Calculation Example

For a typical 2-year-old weighing approximately 12-13 kg:

• Standard dose (45 mg/kg/day): 540-585 mg/day = approximately 270-290 mg every 12 hours 1
• High dose (90 mg/kg/day): 1,080-1,170 mg/day = approximately 540-585 mg every 12 hours 1

Critical Dosing Considerations

When to Use High-Dose Therapy

• The 90 mg/kg/day regimen is designed to overcome penicillin-resistant Streptococcus pneumoniae, the most common bacterial cause of serious respiratory infections 2
• High-dose amoxicillin maintains therapeutic concentrations above the MIC for resistant organisms 3

FDA-Approved Dosing

• The FDA label confirms that for severe infections or lower respiratory tract infections, 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours is appropriate 4
• For severe infections, 875 mg every 12 hours or 500 mg every 8 hours for adults, with pediatric dosing scaled by weight 4

Common Pitfalls to Avoid

• Do not use three-times-daily dosing at lower doses when twice-daily high-dose therapy is indicated—twice-daily dosing at 90 mg/kg/day improves adherence and achieves superior pharmacokinetic profiles 2
• Do not exceed 4,000 mg/day total regardless of calculated weight-based dose 1
• Ensure dosing is weight-based, not age-based—a 2-year-old's weight can vary significantly (typically 10-15 kg) 1

Treatment Duration and Monitoring

• Continue treatment for a minimum of 48-72 hours beyond symptom resolution 1
• For Streptococcus pyogenes infections, treat for at least 10 days to prevent acute rheumatic fever 4
• Children should show clinical improvement within 48-72 hours; if not, reevaluation is necessary 1