Amoxicillin Dosage for Community-Acquired Pneumonia in Children
For children with community-acquired pneumonia, the recommended dosage of amoxicillin is 90 mg/kg/day divided into two doses, with a maximum of 4 g/day. 1
Dosage Recommendations Based on Age and Severity
Standard Dosing
- For mild to moderate infections: 45 mg/kg/day divided into 2 doses 1
- For moderate to severe infections: 80-90 mg/kg/day divided into 2 doses 1
- Maximum daily dose: 90 mg/kg/day, not to exceed 4 g/day 1
Risk Factors Requiring Higher Dosing (80-90 mg/kg/day)
- Age younger than 2 years
- Attendance at childcare
- Antimicrobial treatment within previous 30 days
- Living in communities with high prevalence of resistant S. pneumoniae (>10%) 1
Treatment Duration
The American Academy of Pediatrics recommends:
- Uncomplicated pneumococcal pneumonia: 5-7 days 1
- Bacteremic pneumococcal pneumonia: 10-14 days 1
- Severe pneumonia: 10 days, extended to 14-21 days for complicated cases 1
Recent clinical trials have demonstrated that shorter courses may be effective:
- The CAP-IT trial showed that a 5-day course of amoxicillin was non-inferior to a 10-day course for children with CAP 2
- The SCOUT-CAP trial found that a 5-day antibiotic strategy was superior to a 10-day strategy, with similar clinical response and fewer antibiotic resistance genes 3
Administration Guidelines
- Twice-daily dosing (every 12 hours) provides comparable drug exposure to three-times-daily dosing for most common pathogens 1
- No dose adjustment needed unless severe renal impairment is present (GFR <30 mL/min) 1
Monitoring and Follow-up
- Assess for clinical improvement within 48-72 hours 1
- Signs of improvement include:
- Decreased respiratory rate
- Reduced work of breathing
- Improved oxygen saturation
- Decreased fever
- Improved feeding 1
- Review within 48 hours if not improving, and consider switching to a second-line antibiotic such as amoxicillin-clavulanate 1
Special Considerations
- For children with beta-lactam allergy, macrolides are the recommended alternative 1
- Macrolides (azithromycin, clarithromycin) may be used for children over 5 years old or if Mycoplasma or Chlamydia infection is suspected 1
Important Clinical Pitfalls
Underdosing risk: Using lower doses (35-50 mg/kg/day) may be inadequate for areas with high pneumococcal resistance. While the CAP-IT trial found similar outcomes between lower and higher doses 2, the AAP guidelines recommend the higher dose (80-90 mg/kg/day) for children with risk factors for resistant organisms 1.
Treatment duration: While traditional practice has been 10-day treatment, evidence now supports 5-day treatment for uncomplicated CAP in children who show early clinical improvement 3, 4. A 3-day course has been associated with unacceptable failure rates and should be avoided 5.
Adherence concerns: Twice-daily dosing may improve adherence compared to three-times-daily dosing while maintaining efficacy 1.