Amoxicillin Dosing for Otitis Media
High-dose amoxicillin at 80-90 mg/kg/day divided into 2 doses is the recommended first-line treatment for acute otitis media in children. 1, 2
Standard Dosing Regimen
- Administer 80-90 mg/kg/day divided into 2 daily doses for most pediatric patients with acute otitis media 1, 2
- This high-dose regimen achieves middle ear fluid concentrations that exceed the minimum inhibitory concentration (MIC) for intermediately resistant Streptococcus pneumoniae and many highly resistant serotypes throughout the dosing interval 3, 2
- Approximately 87% of S. pneumoniae isolates are susceptible to high-dose amoxicillin, compared to only 83% with standard-dose (40-45 mg/kg/day) therapy 3, 2
- The twice-daily dosing schedule is as effective as three-times-daily administration and improves adherence by reducing scheduling difficulties for caregivers 4, 5
When to Use Amoxicillin-Clavulanate Instead
Switch to high-dose amoxicillin-clavulanate (90 mg/kg/day of amoxicillin with 6.4 mg/kg/day of clavulanate in a 14:1 ratio, divided into 2 doses) in these specific situations: 1, 2
- Child received amoxicillin within the previous 30 days 1, 2
- Concurrent purulent conjunctivitis is present 1, 2
- Coverage for β-lactamase-producing Haemophilus influenzae or Moraxella catarrhalis is specifically desired 3, 2
- The 14:1 ratio formulation causes less diarrhea than other amoxicillin-clavulanate preparations 3, 2
Treatment Duration
- Treat children under 2 years of age for 10 days 2
- Older children may receive shorter courses based on clinical judgment, though 10 days remains standard 2
Managing Treatment Failure
If no clinical improvement occurs within 48-72 hours: 1, 2
- Switch from amoxicillin to high-dose amoxicillin-clavulanate (90 mg/kg/day of amoxicillin with 6.4 mg/kg/day of clavulanate in 2 divided doses) 1
- Alternatively, administer ceftriaxone 50 mg IM or IV daily for 3 days 1
- Reassess the diagnosis to ensure acute otitis media is still the correct diagnosis 2
Penicillin-Allergic Patients
For children with penicillin allergy, use: 1
- Cefdinir 14 mg/kg/day in 1 or 2 doses, OR
- Cefuroxime 30 mg/kg/day in 2 divided doses, OR
- Cefpodoxime 10 mg/kg/day in 2 divided doses 1
Important Clinical Caveats
- In obese children, do not exceed the standard adult maximum dose of 1500 mg/day despite weight-based calculations suggesting higher doses, as this remains a point of clinical debate among guideline authors 6
- High-dose amoxicillin provides no additional benefit over standard-dose in children at low risk for antibiotic-resistant bacteria, but since resistance patterns cannot be predicted clinically, high-dose remains the standard recommendation 7
- Pain management should be addressed regardless of antibiotic choice 2
- The rationale for high-dose therapy is based on evolving bacterial resistance patterns, particularly non-vaccine serotypes of S. pneumoniae that have increased following widespread PCV7 and PCV13 vaccination 3