Augmentin Dosing for Mild Tooth/Face Cellulitis in a 7-Year-Old, 25.4 kg Patient
For this 7-year-old patient weighing 25.4 kg with mild tooth/face cellulitis, the recommended dose is 45 mg/kg/day of the amoxicillin component divided into two doses (approximately 570 mg twice daily), which translates to approximately 6.7 mL of the 600-42.9 mg/5mL suspension twice daily for 7-10 days. 1, 2
Weight-Based Calculation
- For a 25.4 kg child, the standard dose calculation is: 25.4 kg × 45 mg/kg/day = 1,143 mg/day total, divided into 2 doses = 571.5 mg per dose 1, 2
- Using the 600-42.9 mg/5mL formulation (which contains 600 mg amoxicillin per 5 mL), each dose of approximately 570 mg requires roughly 4.75 mL, but rounding to 5 mL (600 mg) twice daily is clinically appropriate and simplifies administration 2
- Alternatively, you could dose at 6.7 mL twice daily to achieve closer to the calculated 570 mg per dose 1
Rationale for Standard-Dose Regimen
- The 45 mg/kg/day regimen is appropriate for mild cellulitis without risk factors for resistant organisms 1, 2
- This dosing provides adequate coverage for Streptococcus pyogenes and non-β-lactamase-producing organisms commonly involved in odontogenic infections 1, 3
- The combination of amoxicillin with clavulanic acid is specifically indicated for facial cellulitis because it covers β-lactamase-producing Staphylococcus aureus and oral anaerobes 3, 4
When to Consider High-Dose Therapy (90 mg/kg/day)
High-dose therapy would be indicated if this patient had any of the following risk factors, but these do NOT appear to be present based on the "mild" designation 2:
- Recent antibiotic use within the past 30 days 2, 5
- Daycare attendance 2, 5
- Age less than 2 years 2
- Moderate to severe infection 2, 5
- Geographic area with high prevalence of penicillin-resistant S. pneumoniae (>10%) 2, 5
Treatment Duration and Monitoring
- Continue treatment for 7-10 days for most soft tissue infections 1, 2
- Clinical improvement should be evident within 48-72 hours; if no improvement occurs, reevaluation is necessary 1, 2
- For odontogenic infections specifically, amoxicillin/clavulanic acid has demonstrated superior outcomes compared to amoxicillin alone, with shorter hospital stays and better pain control 3, 4
Critical Dosing Considerations
- The maximum daily dose of amoxicillin should not exceed 4000 mg/day regardless of weight 1
- Administer at the start of meals to minimize gastrointestinal intolerance 6
- Shake the oral suspension well before each use 6
- The reconstituted suspension must be discarded after 14 days; refrigeration is preferable but not required 6
Common Pitfalls to Avoid
- Do not underdose: Using insufficient doses fails to achieve adequate tissue concentrations and promotes antimicrobial resistance 2
- Verify the suspension concentration: The 600-42.9 mg/5mL formulation is different from standard 250/62 or 125/31 formulations, so volume calculations must be adjusted accordingly 2
- Do not use the 875 mg tablet formulation: This patient weighs less than 40 kg and should receive weight-based liquid suspension dosing 6