What is the recommended dose of Augmentin (amoxicillin/clavulanate) for an 11 kg child with persistent otitis media?

Augmentin Dosing for Persistent Otitis Media in an 11 kg Child

For an 11 kg child with persistent otitis media, prescribe high-dose amoxicillin-clavulanate (Augmentin) 90 mg/kg/day of the amoxicillin component with 6.4 mg/kg/day of clavulanate, divided into 2 doses daily, which equals approximately 495 mg of amoxicillin twice daily (total 990 mg/day). 1

Rationale for High-Dose Amoxicillin-Clavulanate

Persistent otitis media requires coverage for β-lactamase-producing organisms that commonly cause treatment failure after initial amoxicillin therapy. 1

• The 90/6.4 mg/kg/day formulation (14:1 ratio of amoxicillin to clavulanate) provides superior coverage against:

  • β-lactamase-producing Haemophilus influenzae (the predominant cause of amoxicillin failure) 2
  • β-lactamase-producing Moraxella catarrhalis 1
  • Drug-resistant Streptococcus pneumoniae including penicillin-intermediate and some penicillin-resistant strains 1

• This specific 14:1 ratio formulation causes less diarrhea than other amoxicillin-clavulanate preparations, improving tolerability. 1

Practical Prescribing Details

For an 11 kg child, the calculation is:

• 90 mg/kg/day × 11 kg = 990 mg amoxicillin component per day
• Divided into 2 doses = 495 mg twice daily 1

Available formulation: Use Augmentin ES-600 (600 mg amoxicillin/42.9 mg clavulanate per 5 mL), which provides the correct 14:1 ratio. 3, 4

• Dose: approximately 4 mL twice daily

Treatment Duration and Monitoring

• Duration: 10 days for persistent otitis media 1, 5
• Reassessment: Evaluate at 48-72 hours; if no improvement, consider treatment failure and switch to intramuscular ceftriaxone (50 mg/kg/day for 3-5 days) 1

Common Pitfalls to Avoid

• Do not use standard-dose amoxicillin-clavulanate formulations (such as 40/10 mg/kg/day or 45/6.4 mg/kg/day) for persistent otitis media, as they provide inadequate coverage for resistant organisms. 1

• Do not use the 7:1 ratio formulations (higher clavulanate content), as they significantly increase the risk of diarrhea without improving efficacy. 1

• Avoid macrolides (azithromycin, clarithromycin) as they have inferior bacteriologic efficacy, with only 20-25% effectiveness against major AOM pathogens in persistent cases. 1

Evidence for Superior Efficacy

• High-dose amoxicillin-clavulanate achieved 96% eradication of S. pneumoniae from middle ear fluid at days 4-6 of therapy, significantly superior to azithromycin. 1

• In persistent AOM cases, β-lactamase-producing H. influenzae accounts for 64% of bacteriologic failures with amoxicillin monotherapy, making clavulanate essential. 2