Augmentin Dosing for a 98-pound (44.5 kg) 9-Year-Old
For a 9-year-old child weighing 44.5 kg, the appropriate Augmentin dose depends on the infection being treated: for most community-acquired infections use standard-dose amoxicillin-clavulanate 45 mg/kg/day (approximately 2000 mg/day of amoxicillin component) divided twice daily, but for β-lactamase-producing organisms or recent antibiotic exposure use high-dose 90 mg/kg/day (approximately 4000 mg/day of amoxicillin component) divided twice daily.
Dosing Algorithm by Clinical Scenario
For Community-Acquired Pneumonia (CAP)
Standard-dose regimen (45 mg/kg/day):
- This child would receive approximately 1000 mg of amoxicillin component twice daily
- Use when β-lactamase-negative Haemophilus influenzae is suspected 1, 2, 1
- Appropriate for fully immunized children without recent antibiotic exposure 1
High-dose regimen (90 mg/kg/day):
- This child would receive approximately 2000 mg of amoxicillin component twice daily
- Use when β-lactamase-producing organisms are suspected 1, 2, 1
- Required for children with recent antibiotic exposure (within 30 days) 1
- Necessary in areas with >10% penicillin-resistant S. pneumoniae 3
For Acute Otitis Media (AOM)
High-dose is preferred:
- 90 mg/kg/day (approximately 4000 mg/day) divided twice daily 4, 5
- The FDA-approved Augmentin ES-600 formulation provides 90 mg/kg/day dosing 5
- For a 44.5 kg child, this exceeds the maximum recommended dose for ES-600 (designed for children <40 kg) 5
- Use adult-strength tablets: one 875 mg tablet twice daily (provides approximately 39 mg/kg/day of amoxicillin, which is suboptimal)
- Alternative: Use 1000 mg twice daily from standard formulations to approximate higher dosing
For Acute Bacterial Sinusitis
Standard-dose for uncomplicated cases:
- 45 mg/kg/day if child is ≥2 years, no daycare, no recent antibiotics 3
High-dose for risk factors:
- 90 mg/kg/day if <2 years, attends daycare, or recent antibiotic use 3
- This child at 9 years would typically receive standard dosing unless risk factors present
Practical Prescribing for This 44.5 kg Child
Standard-Dose Options:
- Augmentin 875 mg tablet: one tablet twice daily (provides ~39 mg/kg/day)
- Augmentin 500 mg tablet: two tablets twice daily (provides ~45 mg/kg/day) - preferred for accurate dosing
High-Dose Options:
- Augmentin 875 mg tablet: two tablets twice daily (provides ~78 mg/kg/day)
- Augmentin 1000 mg tablet: two tablets twice daily (provides ~90 mg/kg/day) - if available
Critical Caveats
Weight considerations: At 44.5 kg, this child exceeds the weight limit for pediatric suspension formulations like ES-600 (maximum 40 kg) 5. Use adult tablet formulations.
Duration: Treat for 10 days for most respiratory infections 1, 2, 1, though 5-7 days may suffice for mild cases 2.
Timing: Administer at the start of meals to minimize gastrointestinal side effects and enhance clavulanate absorption 5.
β-lactamase coverage: The clavulanate component at 6.4 mg/kg/day (standard in high-dose formulations) adequately inhibits β-lactamase-producing H. influenzae and M. catarrhalis 3, 4.
Resistance patterns: High-dose therapy achieves sinus/middle ear fluid concentrations exceeding the MIC for S. pneumoniae with penicillin MICs up to 4 mcg/mL 6, 7.
Do not substitute formulations: Different Augmentin suspensions contain varying clavulanate concentrations and are not interchangeable 5.