Augmentin Dosing for Otitis Media in a 9-Month-Old
For a 9-month-old infant weighing 9.4 kg with otitis media, prescribe high-dose amoxicillin-clavulanate at 90 mg/kg/day of the amoxicillin component (846 mg/day total) divided into two doses of 423 mg every 12 hours for 10 days. 1
Dose Calculation
- Total daily dose: 9.4 kg × 90 mg/kg = 846 mg of amoxicillin per day 1
- Individual dose: 423 mg every 12 hours (846 mg ÷ 2 doses) 1
- Clavulanate component: 9.4 kg × 6.4 mg/kg = 60.2 mg per day 1
Practical Formulation Selection
Use the 600 mg/5 mL (ES-600) suspension formulation, which provides the optimal 14:1 ratio of amoxicillin to clavulanate. 1 This formulation delivers 600 mg amoxicillin and 42.9 mg clavulanate per 5 mL. 2
Rationale for High-Dose Regimen
This 9-month-old infant has multiple indications for high-dose therapy: 1
- Age <2 years - children under 2 years are at increased risk for complications and resistant organisms 1, 4
- High-dose formulation (90/6.4 mg/kg/day) achieves middle ear fluid concentrations adequate to overcome penicillin-resistant Streptococcus pneumoniae with MICs of 2-4 mg/L 1, 2
- Clinical response rates of 76-95% have been demonstrated with this regimen 1
Administration Instructions
- Give at the start of meals to enhance clavulanate absorption and minimize gastrointestinal intolerance 3
- Twice-daily dosing is associated with significantly less diarrhea compared to three-times-daily regimens 3, 5
- Shake suspension well before each dose 3
Expected Clinical Response
- Clinical improvement should occur within 48-72 hours 1
- If symptoms worsen or fail to improve after 48-72 hours, reassess the patient for treatment failure, complications, or alternative diagnoses 1
- Treatment failure necessitates switching to alternative therapy or further investigation 1
Common Adverse Effects
- Diarrhea occurs in approximately 25% of patients (versus 15% with placebo) 1
- Diaper dermatitis affects approximately 51% (versus 35% with placebo) 1
- The 14:1 ratio formulation (90/6.4 mg/kg/day) causes less diarrhea than other amoxicillin-clavulanate preparations while maintaining efficacy 1
Critical Pitfalls to Avoid
Do not use standard-dose formulations (40-45 mg/kg/day) for this patient. 1 Standard doses fail to achieve adequate concentrations against resistant organisms and lead to treatment failure. 1
Do not substitute different formulations without recalculating doses. 3 The 250/125 mg tablets contain different clavulanate ratios than the 250/62.5 mg chewable tablets and are not interchangeable. 3
Verify the suspension concentration before dispensing - the ES-600 formulation (600 mg/42.9 mg per 5 mL) is specifically designed for high-dose twice-daily therapy. 1, 2