Amoxicillin Dosing for Acute Otitis Media in a 6-Year-Old, 20.6kg Patient
For this 6-year-old patient with an ear infection, administer high-dose amoxicillin at 80-90 mg/kg/day divided into two or three doses, which equals approximately 1650-1850 mg total daily dose (825-925 mg twice daily or 550-617 mg three times daily) for 10 days. 1
Dosing Rationale
High-dose amoxicillin (80-90 mg/kg/day) is the first-line treatment for acute otitis media in children over 6 months of age. 1 This represents a significant increase from older recommendations of 40 mg/kg/day, driven by the emergence of drug-resistant Streptococcus pneumoniae. 2, 3
Specific Calculation for This Patient:
- Patient weight: 20.6 kg
- Recommended dose: 80-90 mg/kg/day
- Total daily dose: 1648-1854 mg/day
- Practical dosing:
- 825 mg twice daily (1650 mg/day total), OR
- 550 mg three times daily (1650 mg/day total)
- Maximum daily dose: 4000 mg/day 1
Treatment Duration
A standard 10-day course is recommended for children 6 years of age with acute otitis media. 1 While 7-day courses may be equally effective for children 2-5 years with mild-to-moderate disease, the standard 10-day duration remains appropriate for this age group. 1
Clinical Context and Severity Considerations
The U.S. guidelines distinguish treatment approaches based on disease severity and recent antibiotic exposure 1:
- For mild disease without recent antibiotic use (past 30 days): High-dose amoxicillin alone is appropriate 1
- For moderate-to-severe disease OR recent antibiotic exposure: High-dose amoxicillin-clavulanate (90 mg/6.4 mg per kg per day) should be considered 1
- Severe disease indicators include: High fever (≥39°C/102.2°F), severe otalgia, or bilateral disease in children under 2 years 1
Common Pitfalls to Avoid
Do not use the outdated 40 mg/kg/day dosing regimen. 2, 3 Research demonstrates that this lower dose is inadequate for eradicating resistant S. pneumoniae, particularly during viral coinfection, with middle ear fluid concentrations insufficient to overcome resistant organisms. 2
Reassess at 48-72 hours if no clinical improvement occurs. 1 Treatment failure at this point should prompt switching to amoxicillin-clavulanate or an alternative agent, as the predominant cause of high-dose amoxicillin failure is beta-lactamase-producing Haemophilus influenzae (present in approximately 34% of cases). 3
Alternative Agents (If Needed)
If the patient has received amoxicillin in the previous 30 days or presents with otitis-conjunctivitis syndrome, initiate high-dose amoxicillin-clavulanate (90 mg/6.4 mg per kg per day) instead of amoxicillin alone. 1
For true penicillin allergy (non-Type I hypersensitivity reactions like rash), cefdinir, cefpodoxime proxetil, or cefuroxime axetil are appropriate alternatives. 1 For immediate Type I hypersensitivity reactions to beta-lactams, azithromycin or clarithromycin may be used, though these have limited effectiveness with 20-25% bacterial failure rates. 1