What is the recommended dose of amoxicillin (amoxicillin) for a baby with otitis media weighing 7.67 kg?

Amoxicillin Dosing for a 7.67 kg Baby with Otitis Media

For a 7.67 kg baby with acute otitis media, administer amoxicillin 80-90 mg/kg/day divided into two doses every 12 hours, which equals 307-345 mg per dose (614-690 mg total daily dose). 1

Dose Calculation

• Weight-based dosing: Using the American Academy of Pediatrics recommended high-dose regimen of 80-90 mg/kg/day 2, 1:

  • 7.67 kg × 80 mg/kg = 614 mg/day (307 mg every 12 hours)
  • 7.67 kg × 90 mg/kg = 690 mg/day (345 mg every 12 hours)

• Practical dosing with available formulations: Amoxicillin oral suspension is typically available as 125 mg/5 mL or 250 mg/5 mL 3

  • For 307 mg dose: approximately 12.3 mL of 125 mg/5 mL suspension OR 6.1 mL of 250 mg/5 mL suspension
  • For 345 mg dose: approximately 13.8 mL of 125 mg/5 mL suspension OR 6.9 mL of 250 mg/5 mL suspension

Rationale for High-Dose Therapy

High-dose amoxicillin (80-90 mg/kg/day) is strongly recommended over standard-dose (40-45 mg/kg/day) for acute otitis media to overcome drug-resistant Streptococcus pneumoniae. 1

• This dosing achieves adequate middle ear fluid concentrations to eradicate resistant organisms with altered penicillin-binding proteins 1
• Standard-dose amoxicillin (40 mg/kg/day) produces inadequate middle ear fluid concentrations, particularly when viral coinfection is present 4
• Research demonstrates that amoxicillin 40 mg/kg/day is insufficient to effectively eradicate resistant S. pneumoniae, with recommendations supporting 75-90 mg/kg/day 4

Dosing Schedule and Duration

• Frequency: Divide total daily dose into 2 equal doses given every 12 hours 1, 3
• Duration: 10 days of therapy 2, 1, 3
• Administration: Can be given without regard to meals, though administration with meals may improve gastrointestinal tolerability 2

Clinical Considerations

The every 12-hour dosing regimen is preferred because it significantly reduces diarrhea compared to every 8-hour dosing. 3

• Clinical trials demonstrate diarrhea incidence of 14% with every 12-hour dosing versus 34% with every 8-hour dosing 3
• Severe diarrhea or withdrawal due to diarrhea occurred in 3% with every 12-hour dosing versus 8% with every 8-hour dosing 3

Treatment Failure Management

Reassess the patient if symptoms worsen or fail to improve within 48-72 hours. 1

• If treatment fails, switch to high-dose amoxicillin-clavulanate (90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day clavulanate in 2 divided doses) 1
• Beta-lactamase-producing Haemophilus influenzae is the predominant pathogen in amoxicillin treatment failures 5
• Bacteriologic failure occurs in approximately 28% of patients, with 64% of failures due to beta-lactamase-positive H. influenzae 5

Pain Management

Address pain management regardless of antibiotic use, especially during the first 24 hours. 1

Common Pitfalls to Avoid

• Do not use standard-dose amoxicillin (40-45 mg/kg/day) in areas with >10% penicillin-nonsusceptible S. pneumoniae or in children <2 years old 2, 1
• Do not substitute two 250 mg tablets for one 500 mg tablet of amoxicillin-clavulanate formulations, as clavulanate content differs 3
• Do not use amoxicillin-clavulanate as first-line therapy unless the child received amoxicillin in the previous 30 days or has otitis-conjunctivitis syndrome 2