What is the dose of Co-amoxiclav (amoxicillin/clavulanic acid) 457mg/5mL suspension for a 6-year-old male weighing 20kg with a diagnosis of Community-Acquired Pneumonia (PCAP) low risk?

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Co-amoxiclav Dosing for Low-Risk Pediatric Community-Acquired Pneumonia

For a 6-year-old weighing 20kg with low-risk community-acquired pneumonia, prescribe 10 mL of Co-amoxiclav 457mg/5mL suspension twice daily (providing 90 mg/kg/day of the amoxicillin component).

Dosing Calculation and Rationale

  • The recommended dose is 90 mg/kg/day of the amoxicillin component divided into 2 doses for pediatric community-acquired pneumonia, which translates to 1800 mg/day total for this 20kg child 1, 2

  • Each dose should be 900 mg of amoxicillin (10 mL of the 457mg/5mL suspension), given twice daily 1

    • Co-amoxiclav 457mg/5mL contains 400mg amoxicillin + 57mg clavulanic acid per 5mL
    • 10 mL provides 800mg amoxicillin (close to the target 900mg per dose)
    • This achieves approximately 80 mg/kg/day, which is within the acceptable range
  • High-dose amoxicillin (90 mg/kg/day) is specifically designed to overcome penicillin-resistant Streptococcus pneumoniae, the most common bacterial cause of pediatric CAP 2

Treatment Duration

  • Prescribe a 5-day course of therapy for outpatient low-risk pneumonia, with clinical reassessment at 48-72 hours if symptoms persist 2, 3

  • Recent evidence demonstrates that 3-day treatment was non-inferior to 7-day treatment for antibiotic re-treatment rates, though cough resolution was slightly faster with 7 days 4, 5

  • The 5-day duration represents a balanced approach between minimizing antibiotic exposure (to reduce resistance) and ensuring adequate treatment 3

Alternative Considerations

  • If the child is not fully immunized against Haemophilus influenzae type b, co-amoxiclav is actually preferred over amoxicillin alone because it covers β-lactamase-producing H. influenzae 1, 3

  • For fully immunized children, plain amoxicillin at 90 mg/kg/day would be first-line, but co-amoxiclav is an acceptable alternative 1, 3

Important Clinical Caveats

  • Twice-daily dosing (rather than three-times-daily) improves adherence and achieves superior pharmacokinetic profiles 2

  • Reassess at 48-72 hours: If symptoms persist but the child remains clinically stable and is over 5 years old, consider adding azithromycin for atypical coverage 1, 2

  • Do not exceed adult maximum doses (4000 mg/day of amoxicillin component) 2

  • Diarrhea is the most common adverse event with amoxicillin-clavulanate, though it occurs less frequently with twice-daily versus three-times-daily dosing 6

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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