Antibiotic Prescription for a 15-Month-Old with Acute Otitis Media
For a 15-month-old child with an ear infection, prescribe high-dose amoxicillin at 80-90 mg/kg/day divided into two doses (given every 12 hours) for 10 days, taken at the start of meals. 1, 2
First-Line Treatment Regimen
High-dose amoxicillin (80-90 mg/kg/day) divided every 12 hours is the recommended first-line antibiotic for acute otitis media in children aged 3 months and older 1, 2
For a 15-month-old weighing approximately 10-12 kg, this translates to roughly 800-1080 mg total daily dose, or 400-540 mg per dose twice daily 2
The medication should be administered at the start of a meal to minimize gastrointestinal intolerance 2
Treatment duration should be 10 days for acute otitis media in this age group 1, 3
When to Use Alternative First-Line Therapy
Switch to high-dose amoxicillin-clavulanate (90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day of clavulanate in a 14:1 ratio, divided twice daily) if: 1
- The child has taken amoxicillin in the previous 30 days 1
- There is concurrent purulent conjunctivitis 1
- Coverage for β-lactamase-producing H. influenzae or M. catarrhalis is specifically desired 1
Rationale for High-Dose Therapy
High-dose amoxicillin achieves middle ear fluid levels that exceed the minimum inhibitory concentration (MIC) for approximately 83-87% of S. pneumoniae isolates, including intermediately resistant strains 1
The standard 40 mg/kg/day dosing is inadequate to effectively eradicate resistant S. pneumoniae, particularly during viral coinfection 4
High-dose amoxicillin-clavulanate demonstrated 96% eradication of S. pneumoniae from middle ear fluid at days 4-6 of therapy 1
Essential Pain Management
Analgesics (acetaminophen or ibuprofen) should be prescribed regardless of antibiotic use and continued as long as needed for pain relief 5, 6
Pain management is considered essential in AOM treatment, independent of the decision to use antibiotics 5
Prescription Format Example
Amoxicillin oral suspension 400 mg/5 mL:
- Dose: [Calculate based on child's weight: 80-90 mg/kg/day ÷ 2]
- Give [calculated dose in mL] by mouth every 12 hours for 10 days
- Administer at the start of meals
- Shake well before each use
- Refrigeration preferable but not required; discard after 14 days 2
Follow-Up Instructions
Reassess within 48-72 hours if symptoms worsen or fail to improve 5, 6
If treatment fails after 48-72 hours, switch to high-dose amoxicillin-clavulanate as second-line therapy 1
Continue treatment for minimum 48-72 hours beyond symptom resolution 2
Critical Pitfalls to Avoid
Do not use two 250 mg/125 mg amoxicillin-clavulanate tablets to substitute for one 500 mg/125 mg tablet - they contain the same amount of clavulanate but different amoxicillin amounts, making them non-equivalent 3
Do not prescribe the 875 mg dose formulation in children under 40 kg 2
Avoid using regular-dose amoxicillin (40 mg/kg/day) as it provides inadequate coverage against resistant pathogens 1, 4
Do not use azithromycin as first-line therapy - it has inferior efficacy compared to high-dose amoxicillin-clavulanate for S. pneumoniae eradication 1