What is the appropriate dose of Augmentin (amoxicillin/clavulanate) for a 9-year-old patient weighing 95 pounds with normal renal function and no known allergies?

Augmentin Dosing for a 95-Pound 9-Year-Old

For a 9-year-old weighing 95 pounds (43 kg), administer Augmentin 45 mg/kg/day of the amoxicillin component divided into two daily doses for standard infections, or 90 mg/kg/day divided into two daily doses for moderate-to-severe infections, recent antibiotic exposure, or suspected drug-resistant pathogens. 1, 2

Weight-Based Calculation

• 95 pounds equals approximately 43 kg 2
• Pediatric dosing must be calculated using weight-based formulas (mg/kg) rather than adult fixed doses for children under 40 kg, though this patient exceeds 40 kg and can use either approach 3, 4

Standard Dosing Regimen (Mild Infections)

• For mild infections without recent antibiotic use (past 4-6 weeks), administer 45 mg/kg/day divided into two doses, which equals approximately 1,935 mg/day total amoxicillin (approximately 970 mg twice daily). 1, 2
• This can be given as 875 mg tablets twice daily, which provides 1,750 mg/day and is within the appropriate range 4
• Standard dosing is appropriate for mild disease in patients without risk factors for resistant pathogens, including no recent antibiotic exposure, no daycare attendance, and age over 2 years 1

High-Dose Regimen (Moderate-to-Severe Infections)

• For moderate-to-severe infections, recent antibiotic use within 4-6 weeks, daycare attendance, or suspected drug-resistant Streptococcus pneumoniae, administer 90 mg/kg/day divided into two doses, which equals approximately 3,870 mg/day total amoxicillin (approximately 1,935 mg twice daily). 1, 2
• This high-dose regimen provides adequate sinus and middle ear fluid concentrations to overcome penicillin-resistant S. pneumoniae 1
• The clavulanate component should be 6.4 mg/kg/day, which equals approximately 275 mg/day for this patient 1

Infection-Specific Considerations

• For acute bacterial sinusitis with moderate disease or recent antibiotic exposure, use the 90 mg/kg/day regimen (approximately 1,935 mg twice daily). 1
• For community-acquired pneumonia with suspected drug-resistant pathogens, the high-dose regimen (90 mg/kg/day) is recommended 2
• Lower respiratory tract infections require 875 mg every 12 hours or 500 mg every 8 hours for patients weighing more than 40 kg 4

Treatment Duration

• Continue treatment for 7-10 days for most infections, with duration based on clinical response 2
• For sinusitis, treatment may extend to 14 days depending on clinical response 2
• Continue therapy for at least 48-72 hours beyond symptom resolution or evidence of bacterial eradication 4

Critical Pitfalls to Avoid

• Do not underdose when drug-resistant pathogens are suspected—use the 90 mg/kg/day regimen for recent antibiotic exposure (within 4-6 weeks), daycare attendance, or treatment failure. 1, 2
• Do not use the 875 mg dose if severe renal impairment is present (GFR <30 mL/min) 4
• Ensure the patient takes medication at the start of a meal to minimize gastrointestinal intolerance 4
• For Streptococcus pyogenes infections, treat for at least 10 days to prevent acute rheumatic fever 4

Practical Formulation Selection

• For standard dosing (45 mg/kg/day): Use 875 mg tablets twice daily 4
• For high-dose regimen (90 mg/kg/day): This patient would require approximately 1,935 mg twice daily, which may necessitate using liquid suspension or multiple tablets, as standard tablet strengths may not provide exact dosing 1, 2
• The 90/6.4 mg/kg/day formulation maintains appropriate amoxicillin-to-clavulanate ratios for enhanced coverage 5, 6