What is the appropriate dosage of Amoxicillin (Amox)-Clavulanate for a 15-month-old child weighing 22 pounds with Acute Otitis Media (AOM)?

Amoxicillin-Clavulanate Dosing for 15-Month-Old with AOM

For a 15-month-old child weighing 22 pounds (10 kg) with acute otitis media, administer high-dose amoxicillin-clavulanate at 90 mg/kg/day of the amoxicillin component, which equals 900 mg/day divided into two doses of 450 mg twice daily, using the 14:1 ratio formulation (90 mg/kg amoxicillin with 6.4 mg/kg clavulanate). 1

Specific Dosing Calculation

• Weight conversion: 22 pounds = 10 kg 1
• Total daily dose: 90 mg/kg/day × 10 kg = 900 mg amoxicillin per day 1
• Divided dose: 900 mg ÷ 2 = 450 mg amoxicillin per dose, given twice daily 1
• Clavulanate component: 6.4 mg/kg/day × 10 kg = 64 mg clavulanate per day (32 mg per dose) 1

Formulation Selection

• Use the high-dose suspension formulation (400 mg/5 mL or 600 mg/5 mL) to achieve the 14:1 ratio of amoxicillin to clavulanate 1, 2
• The 14:1 ratio formulation significantly reduces diarrhea compared to older formulations with higher clavulanate ratios 1
• Practical dosing: Approximately 5.6 mL of the 400 mg/5 mL suspension twice daily would deliver 448 mg amoxicillin per dose 3

Rationale for High-Dose Therapy in This Patient

• Children younger than 2 years are at increased risk for resistant organisms and should receive high-dose amoxicillin-clavulanate as first-line therapy 1
• At 15 months of age, this patient falls into the high-risk category requiring aggressive initial treatment 1
• High-dose therapy achieves middle ear fluid concentrations exceeding the minimum inhibitory concentration for approximately 87% of Streptococcus pneumoniae isolates, including intermediately resistant strains 1, 4

Treatment Duration and Monitoring

• Standard duration: 10 days of therapy 1, 3
• Expected response: Clinical improvement should be evident within 48-72 hours 1
• Treatment failure: If no improvement or worsening occurs within 48-72 hours, switch to ceftriaxone 50 mg/kg IM/IV 1, 2

Critical Pitfalls to Avoid

• Do not use lower-dose formulations (45 mg/kg/day or 40 mg/kg/day) for this age group, as inadequate dosing of the amoxicillin component when treating potentially resistant organisms is a common pitfall 1
• Do not substitute tablet formulations: The 250 mg/125 mg tablets contain different clavulanate ratios and are not appropriate for children under 40 kg 3
• Do not use three-times-daily dosing: The twice-daily regimen is associated with significantly less diarrhea while maintaining equivalent efficacy 3, 5

Additional Considerations

• Address pain management with analgesics regardless of antibiotic therapy 2
• If the child had received amoxicillin within the previous 30 days, this high-dose amoxicillin-clavulanate choice is further supported over amoxicillin alone 1
• High-dose amoxicillin-clavulanate demonstrates 96% eradication of S. pneumoniae including 91% eradication of penicillin-resistant strains (MICs 2-4 mcg/mL) 4