What is the first-line treatment for pediatric community-acquired pneumonia (CAP)?

First-Line Treatment for Pediatric Community-Acquired Pneumonia

Amoxicillin 90 mg/kg/day divided into 2 doses (maximum 4000 mg/day) is the first-line treatment for previously healthy, appropriately immunized children with mild to moderate community-acquired pneumonia, regardless of age from infancy through adolescence. 1

Treatment Algorithm by Age and Clinical Setting

Preschool Children (< 5 years old) - Outpatient

• Oral amoxicillin 90 mg/kg/day in 2 divided doses is the definitive first-line therapy for previously healthy, fully immunized infants and preschool children with suspected bacterial CAP 1, 2
• Antimicrobial therapy is not routinely required for preschool-aged children with CAP, as viral pathogens cause the majority of cases in this age group 1
• However, when bacterial pneumonia is suspected based on clinical presentation (high fever, focal findings, elevated inflammatory markers), amoxicillin provides optimal coverage against Streptococcus pneumoniae, the most important invasive bacterial pathogen 1
• Treatment duration should be 5 days for uncomplicated cases, as this is equally effective as 10-day courses 3

School-Aged Children and Adolescents (≥ 5 years) - Outpatient

• Oral amoxicillin 90 mg/kg/day in 2 divided doses (maximum 4000 mg/day) remains first-line for typical bacterial pneumonia 1
• Add a macrolide antibiotic (azithromycin 10 mg/kg day 1, then 5 mg/kg days 2-5; maximum 500 mg day 1, then 250 mg days 2-5) when atypical pathogens are suspected based on clinical presentation (gradual onset, prominent cough, lack of toxicity) 1
• For children > 7 years old, doxycycline 2-4 mg/kg/day in 2 doses is an alternative to macrolides for atypical coverage 2
• The British Thoracic Society suggests macrolides may be used as first-line empirical treatment in children ≥ 5 years given the higher prevalence of Mycoplasma pneumoniae in this age group 1

Key Clinical Distinction: The decision to use amoxicillin alone versus adding macrolide coverage depends on clinical presentation. Typical bacterial pneumonia presents with abrupt onset, high fever, focal findings, and toxicity—use amoxicillin alone. Atypical pneumonia presents with gradual onset, prominent dry cough, minimal fever, and diffuse findings—add macrolide coverage. 1

Hospitalized Children - Inpatient

• Ampicillin (150-200 mg/kg/day IV every 6 hours) or penicillin G (200,000-250,000 units/kg/day IV every 4-6 hours) for fully immunized children when local penicillin resistance in invasive S. pneumoniae is minimal 1
• Ceftriaxone (50-100 mg/kg/day IV every 12-24 hours) or cefotaxime (150 mg/kg/day IV every 8 hours) for children who are not fully immunized, in regions with significant penicillin resistance, or for life-threatening infections including empyema 1
• Add vancomycin (40-60 mg/kg/day IV every 6-8 hours) or clindamycin (40 mg/kg/day IV every 6-8 hours) when community-associated MRSA is suspected based on necrotizing pneumonia, empyema, or severe illness 1, 4
• Add azithromycin (10 mg/kg IV on days 1-2, then oral) to β-lactam therapy when atypical pathogens cannot be excluded 1

Penicillin Allergy Considerations

• For non-severe, non-immediate penicillin reactions, consider oral cephalosporins (cefpodoxime, cefprozil, or cefuroxime) under medical supervision 1, 5
• For severe penicillin allergy, use levofloxacin 8-10 mg/kg/day once daily (maximum 750 mg/day) or azithromycin 5
• Approximately 10% of penicillin-allergic patients may cross-react with cephalosporins, so avoid cephalosporins in severe or immediate-type reactions 5
• Clindamycin or linezolid are alternatives if local susceptibility data support their use 1

Treatment Duration

• 5 days of amoxicillin is equally effective as 10 days for uncomplicated CAP in children 6 months to 10 years old treated as outpatients 3
• Treatment should not exceed 7 days for uncomplicated cases 6
• Parapneumonic effusions require 2-4 weeks of antibiotics depending on adequacy of drainage and clinical response 2

Clinical Monitoring and Reassessment

• Children should demonstrate clinical improvement within 48-72 hours of initiating appropriate antibiotic therapy 1, 2, 6
• Reassessment is mandatory at 48-72 hours if fever persists, respiratory distress worsens, or clinical deterioration occurs 1, 2
• Repeat chest radiography is indicated only for patients with worsening symptoms, persistent fever beyond 48-72 hours, or suspected complications 1, 2

Common Pitfalls to Avoid

• Do not routinely prescribe antibiotics for preschool-aged children with CAP, as most cases are viral 1
• Do not use ciprofloxacin for CAP, as it lacks adequate pneumococcal coverage 5
• Do not delay influenza antiviral therapy (oseltamivir) when influenza is suspected during local circulation, even without confirmatory testing 1
• Do not use vancomycin or other non-β-lactam agents as monotherapy when penicillin resistance is a concern; third-generation cephalosporins remain highly effective for the degree of resistance currently seen in North America 1
• Do not stop antibiotics early even if clinical improvement occurs after 3 days; complete the full 5-day course 3

Special Considerations for Influenza

• Oseltamivir should be administered as soon as possible to children with moderate to severe CAP consistent with influenza during local circulation, without waiting for confirmatory testing 1
• Treatment provides maximal benefit when started within 48 hours but may still benefit those with severe disease beyond 48 hours 1