What is the recommended dose of Augmentin (amoxicillin/clavulanate) in tablet form for a 38kg child with normal renal function and no known allergies to penicillin or clavulanate?

Augmentin Dosing for a 38kg Child in Tablet Form

For a 38kg child with normal renal function, the recommended Augmentin dose is 45 mg/kg/day of the amoxicillin component divided into two doses (approximately 855mg twice daily) for mild-to-moderate infections, or 90 mg/kg/day divided into two doses (approximately 1710mg twice daily) for severe infections or when resistant organisms are suspected, with an absolute maximum of 2000mg per dose. 1, 2

Weight-Based Dosing Algorithm

Standard-Dose Regimen (Mild-to-Moderate Infections)

• Calculate 45 mg/kg/day: 38kg × 45 mg/kg = 1,710mg total daily dose 1
• Divide into 2 doses: 855mg per dose, given every 12 hours 1
• This can be administered as one 875mg/125mg tablet twice daily 2
• This regimen provides adequate coverage for most susceptible pathogens including Streptococcus pneumoniae, Haemophilus influenzae (non-β-lactamase producing), and Streptococcus pyogenes 1

High-Dose Regimen (Severe Infections or Resistant Organisms)

• Calculate 90 mg/kg/day: 38kg × 90 mg/kg = 3,420mg total daily dose 1
• Divide into 2 doses: 1,710mg per dose, given every 12 hours 1
• This requires two 875mg/125mg tablets per dose (1750mg), twice daily 2
• The absolute maximum single dose is 2000mg per dose, so this dosing is within safe limits 1

Indications for High-Dose Therapy

Use the 90 mg/kg/day regimen if ANY of the following risk factors are present: 1

• Age <2 years (not applicable here, but included for completeness)
• Daycare attendance 1
• Recent antibiotic use within the past 30 days 1
• Geographic area with >10% penicillin-resistant S. pneumoniae 1
• Incomplete Haemophilus influenzae type b vaccination 1
• Moderate to severe illness 1
• Concurrent purulent acute otitis media 1

Specific Infection Types

Community-Acquired Pneumonia

• Use 90 mg/kg/day in 2 doses (1710mg per dose) for 10 days 1, 3
• This provides optimal coverage against penicillin-resistant S. pneumoniae and β-lactamase-producing organisms 1

Acute Otitis Media

• Standard dose: 45 mg/kg/day (855mg per dose) for uncomplicated cases 1
• High dose: 90 mg/kg/day (1710mg per dose) for severe AOM, bilateral AOM, or recent antibiotic exposure 1
• Treatment duration: 10 days 1

Acute Bacterial Sinusitis

• Standard dose: 45 mg/kg/day (855mg per dose) without risk factors 3
• High dose: 90 mg/kg/day (1710mg per dose) with risk factors 1

Critical Dosing Considerations

• The absolute maximum daily dose is 4000mg of amoxicillin component regardless of weight 1, 3
• The maximum single dose is 2000mg per dose 1
• Since this child weighs <40kg, pediatric dosing guidelines apply, but tablet formulations are appropriate 2
• Do not substitute two 250mg/125mg tablets for one 500mg/125mg tablet, as they contain different amounts of clavulanic acid 2

Administration and Monitoring

• Administer at the start of meals to minimize gastrointestinal intolerance and enhance clavulanate absorption 2
• Clinical improvement should occur within 48-72 hours of starting therapy 1, 3
• If no improvement or worsening occurs after 72 hours, reevaluate the diagnosis clinically, consider imaging, evaluate for atypical pathogens, and potentially add a macrolide 1

Common Pitfalls to Avoid

• Do not use the 250mg/125mg tablet formulation for this weight, as it is not recommended until the child weighs at least 40kg due to different amoxicillin to clavulanic acid ratios 2
• Do not underdose: Using standard doses when high-dose therapy is indicated leads to treatment failure with resistant organisms 4
• Verify the specific tablet strength before dispensing: The 875mg/125mg tablet is the appropriate formulation for this weight 2
• Most common adverse effect is diarrhea, which occurs less frequently with twice-daily dosing compared to three-times-daily regimens 5