Augmentin 457 mg/5 mL Dosing for a 12-Year-Old Boy Weighing 30 kg
For a 12-year-old boy weighing 30 kg, administer 10 mL of Augmentin 457 mg/5 mL (which provides 914 mg of amoxicillin) twice daily, achieving the recommended high-dose regimen of 90 mg/kg/day for most pediatric infections requiring amoxicillin/clavulanate. 1, 2, 3
Weight-Based Calculation
The standard high-dose regimen for Augmentin is 90 mg/kg/day of the amoxicillin component divided into 2 doses, which is the preferred dosing for community-acquired pneumonia, resistant pathogens, and β-lactamase-producing organisms. 1, 2, 3
For a 30 kg child: 30 kg × 90 mg/kg/day = 2,700 mg/day total, divided into 2 doses = 1,350 mg per dose. 1
Since Augmentin 457 mg/5 mL contains 400 mg amoxicillin per 5 mL (the "457" refers to the total of amoxicillin + clavulanate), you need approximately 11.4 mL per dose to achieve 914 mg of amoxicillin. 4
Practical dosing: Round to 10 mL twice daily (providing 800 mg amoxicillin per dose, or 1,600 mg/day total = 53 mg/kg/day), which is appropriate for mild-to-moderate infections. 5, 2
For severe infections or high-resistance areas: Use 11-12 mL twice daily to approach the 90 mg/kg/day target. 1, 3
Indication-Specific Dosing Guidance
For community-acquired pneumonia or suspected resistant Streptococcus pneumoniae: Use the high-dose regimen of 90 mg/kg/day (approximately 11-12 mL twice daily) to provide optimal coverage against penicillin-resistant strains and β-lactamase-producing Haemophilus influenzae. 5, 1, 3
For β-lactamase-producing H. influenzae infections: The Infectious Diseases Society of America recommends either 45 mg/kg/day in 3 doses OR 90 mg/kg/day in 2 doses of the amoxicillin component. 5, 2
For mild-to-moderate respiratory tract infections, skin infections, or genitourinary infections: The standard dose of 45 mg/kg/day divided into 2 doses (approximately 5-6 mL twice daily) is adequate. 2, 4
Critical Dosing Considerations
Maximum daily dose: Do not exceed 4,000 mg/day of amoxicillin regardless of weight, which would be approximately 25 mL twice daily of this formulation. 2, 3, 4
Treatment duration: Continue therapy for 7-10 days for most respiratory infections, with a minimum of 48-72 hours beyond symptom resolution. 1, 2
Twice-daily dosing is preferred over three-times-daily dosing because it improves adherence and achieves superior pharmacokinetic profiles. 1
Administration and Monitoring
Administer at the start of meals to minimize gastrointestinal intolerance. 4
Shake the oral suspension well before each use. 4
Store reconstituted suspension in the refrigerator (preferred but not required) and discard any unused portion after 14 days. 4
Clinical improvement should be evident within 48-72 hours; if no improvement occurs, reevaluation and consideration of atypical pathogens or treatment failure is necessary. 1, 2
Common Pitfalls to Avoid
Do not confuse the formulation strength: Augmentin 457 mg/5 mL refers to the combined amoxicillin + clavulanate content, not just amoxicillin alone. The actual amoxicillin content is 400 mg/5 mL. 4
Avoid underdosing in severe infections: For pneumonia or suspected resistant pathogens, the 90 mg/kg/day regimen is critical for adequate coverage. 5, 1, 3
Do not use the 875 mg tablet formulation in patients with severe renal impairment (GFR <30 mL/min), though this is less relevant for a healthy 12-year-old. 4