Dosing Recommendation for Augmentin 600/5 in a 38 lb Child
For a child weighing 38 lb (approximately 17 kg), administer 8 mL of Augmentin ES-600 (600 mg/5 mL) twice daily for the appropriate duration based on the specific infection being treated. 1
Calculation and Rationale
The child weighs 38 lb, which converts to approximately 17.3 kg. According to the FDA-approved dosing for Augmentin ES-600:
- Standard dose: 90 mg/kg/day of amoxicillin component, divided every 12 hours 1
- For a 17 kg child: The dosing table indicates 7.5 mL twice daily (for 16 kg) to 9.0 mL twice daily (for 20 kg) 1
- Precise calculation: 17 kg × 90 mg/kg/day = 1,530 mg/day total, or 765 mg per dose
- Volume needed: 765 mg ÷ 120 mg/mL = 6.4 mL per dose
However, the FDA label specifically recommends 7.5 mL twice daily for children in the 16-20 kg weight range 1, which provides slightly higher dosing to ensure adequate coverage.
Clinical Context
This high-dose formulation (90 mg/kg/day) is specifically designed for:
- Recurrent or persistent acute otitis media 1
- Infections where β-lactamase-producing organisms are suspected (H. influenzae, M. catarrhalis) 2, 3
- Coverage of penicillin-resistant S. pneumoniae with MICs ≤ 2 mcg/mL 1
The 600 mg/5 mL formulation provides a 14:1 ratio of amoxicillin to clavulanate (42.9 mg clavulanate per 5 mL), which maintains adequate β-lactamase inhibition while minimizing gastrointestinal side effects compared to older formulations 1, 4.
Administration Instructions
- Give at the start of meals to minimize gastrointestinal intolerance and enhance clavulanate absorption 1
- Shake suspension well before each use 1
- Store reconstituted suspension in refrigerator; stable for 10 days 1
- Duration: Typically 10 days for acute otitis media 1; 7-10 days for other respiratory infections 5
Important Caveats
Do NOT substitute other Augmentin formulations for ES-600, as they contain different amounts of clavulanate and are not interchangeable:
- The 200 mg/5 mL suspension contains only 28.5 mg clavulanate per 5 mL
- The 400 mg/5 mL suspension contains 57 mg clavulanate per 5 mL
- ES-600 contains 42.9 mg clavulanate per 5 mL but with higher amoxicillin concentration 1
Risk factors warranting high-dose therapy include: age < 2 years, daycare attendance, recent antibiotic use within 30 days, or moderate-to-severe illness 6, 7. For children without these risk factors, standard-dose amoxicillin (45 mg/kg/day) may be appropriate as first-line therapy 6.
Most common adverse effects include diarrhea (protocol-defined diarrhea in 12.9% of patients), vomiting (6.9%), and diaper rash (6.1%) 1. The twice-daily dosing of ES-600 results in less diarrhea compared to three-times-daily conventional formulations 1, 8.