Dosing Assessment for Augmentin 600/5 in a 45 lb Child
Yes, 6 mL twice daily of Augmentin ES-600 is safe and appropriate for a 45 lb (approximately 20 kg) child, as this delivers 90 mg/kg/day of amoxicillin, which is the recommended high-dose regimen for resistant bacterial infections.
Dose Calculation and Verification
The child weighs 45 lb, which equals approximately 20.4 kg. According to the FDA label for Augmentin ES-600, the recommended dose is 90 mg/kg/day divided every 12 hours 1.
- Calculation: 20 kg × 90 mg/kg/day = 1,800 mg/day total
- Per dose: 1,800 mg ÷ 2 = 900 mg per dose
- Volume needed: Augmentin ES-600 contains 600 mg amoxicillin per 5 mL
- Therefore: (900 mg ÷ 600 mg) × 5 mL = 7.5 mL per dose
According to the FDA dosing table, a 20 kg child should receive 7.5 mL twice daily, not 6 mL 1. The prescribed 6 mL twice daily would deliver only 72 mg/kg/day (1,440 mg/day), which is below the recommended high-dose regimen but still within therapeutic range for standard dosing.
Clinical Context and Appropriateness
When This Dose is Appropriate:
High-dose amoxicillin-clavulanate (90 mg/kg/day) is specifically indicated for 2, 3, 4:
- β-lactamase producing Haemophilus influenzae infections
- Moderate to severe infections
- Children under 2 years old
- Recent antibiotic exposure (within 30 days)
- Day care attendance
- Failed initial amoxicillin therapy
- Geographic areas with high penicillin-resistant Streptococcus pneumoniae prevalence (>10%)
Safety Considerations:
The prescribed 6 mL dose is safe but suboptimal. While it won't cause harm, it may not provide adequate coverage for resistant pathogens. The Augmentin ES-600 formulation was specifically designed to deliver 90 mg/kg/day with a 14:1 ratio of amoxicillin to clavulanate, minimizing diarrhea while maximizing efficacy against resistant organisms 1, 5.
Recommendation
The dose should be corrected to 7.5 mL twice daily to achieve the intended 90 mg/kg/day dosing for this 20 kg child. If the prescriber intended standard-dose therapy (45 mg/kg/day), then 6 mL twice daily would be excessive, and a different formulation should be used 1.
Key Prescribing Points:
- Administer at the start of meals to minimize gastrointestinal side effects 1
- Shake well before each use 1
- Store refrigerated and discard after 10 days 1
- Use an appropriate measuring device (oral syringe) for accurate dosing 1
- Duration typically 10 days for most indications 2, 3, 4
Common Pitfall:
The most frequent error with Augmentin ES-600 is confusing it with other Augmentin formulations. The ES-600 suspension (600 mg/5 mL with 42.9 mg clavulanate) is not interchangeable with the 200 mg/5 mL or 400 mg/5 mL suspensions due to different clavulanate concentrations 1. Always verify the specific formulation being prescribed.