Dosing for 40 mg/mL Amoxicillin/Clavulanate Suspension
The 40 mg/mL amoxicillin/clavulanate suspension does not exist as a standard formulation - you are likely referring to either the 200 mg/28.5 mg per 5 mL (40 mg/5.7 mg per mL) or 400 mg/57 mg per 5 mL (80 mg/11.4 mg per mL) formulations, which should be dosed at 45 mg/kg/day of the amoxicillin component in 2 divided doses for standard infections, or 90 mg/kg/day in 2 divided doses (maximum 4000 mg/day) for resistant pathogens or severe infections. 1
Standard Dosing Recommendations
For Most Common Infections (Otitis Media, Sinusitis, Skin Infections)
Standard-dose regimen:
- 45 mg/kg/day of amoxicillin component divided into 2 doses (using 14:1 ratio formulation)
- Maximum: 2000 mg/day 2, 3
High-dose regimen (for resistant pathogens or recent antibiotic use):
- 90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day clavulanate in 2 divided doses
- Maximum: 4000 mg/day (e.g., one 2000 mg tablet twice daily) 4, 5, 6, 1
When to Use High-Dose (90 mg/kg/day)
Use the high-dose regimen in these specific situations:
- Child has received antibiotics within the previous 30 days 6, 7
- Child attends daycare 7
- Child is younger than 2 years 7
- Moderate to severe illness at presentation 7
- Concurrent purulent conjunctivitis (otitis-conjunctivitis syndrome) 6
- Geographic area with >10% penicillin-nonsusceptible S. pneumoniae 8, 7
- Coverage needed for β-lactamase-producing H. influenzae or M. catarrhalis 4, 5
Critical Formulation Warning
The different amoxicillin/clavulanate suspensions are NOT interchangeable 1:
- 200 mg/28.5 mg per 5 mL contains 28.5 mg clavulanate per 5 mL
- 400 mg/57 mg per 5 mL contains 57 mg clavulanate per 5 mL
- 600 mg/42.9 mg per 5 mL contains 42.9 mg clavulanate per 5 mL
The 600 mg/42.9 mg per 5 mL formulation provides the optimal 14:1 ratio for high-dose therapy and should not be substituted with other formulations 1.
Specific Infection Dosing
Community-Acquired Pneumonia
- Outpatient (<5 years): 90 mg/kg/day in 2 doses 4, 5
- Outpatient (≥5 years): 90 mg/kg/day in 2 doses (max 4000 mg/day) 5
Acute Otitis Media
- First-line (no risk factors): 45 mg/kg/day in 2 doses 6
- With risk factors: 90 mg/kg/day with 6.4 mg/kg/day clavulanate in 2 doses 6
Acute Bacterial Sinusitis
- Standard (≥2 years, no recent antibiotics): 45 mg/kg/day in 2 doses 7
- High-risk or severe: 80-90 mg/kg/day with 6.4 mg/kg/day clavulanate in 2 doses 7
Skin and Soft Tissue Infections
- Impetigo/cellulitis: 25 mg/kg/day (of amoxicillin component) in 2 divided doses 9, 2, 3
- 875/125 mg twice daily for adults 2, 3
Administration Guidance
Timing: Administer at the start of meals to minimize gastrointestinal intolerance and enhance clavulanate absorption 1
Duration:
- Most infections: 10 days 4, 10, 6, 7
- Acute bacterial sinusitis: Continue for 7 days after symptom resolution (minimum 10 days total) 7
Common Pitfalls to Avoid
Do not substitute formulations - the clavulanate content varies significantly and affects both efficacy and tolerability 1
Do not use standard-dose in high-risk patients - this leads to treatment failure with resistant S. pneumoniae (MIC 2-4 mcg/mL) 6, 7
Do not exceed 6.4 mg/kg/day of clavulanate in children - higher doses increase diarrhea without improving efficacy 1
Shake suspension well before each use - inadequate mixing leads to inconsistent dosing 1
Refrigerate reconstituted suspension and discard after 10 days 1