What is the dosage of amoxicillin (amoxicillin-clavulanate) in pediatric patients?

Amoxicillin-Clavulanate Dosing in Pediatric Patients

The standard dosage of amoxicillin-clavulanate for pediatric patients is 45 mg/kg/day of the amoxicillin component divided into 3 doses or 90 mg/kg/day divided into 2 doses for β-lactamase producing organisms. 1

Age-Based Dosing Recommendations

Neonates and Infants <12 weeks (<3 months)

• 30 mg/kg/day divided every 12 hours, based on the amoxicillin component 2
• Use of the 125 mg/5 mL oral suspension is recommended for this age group 2

Patients ≥12 weeks (≥3 months)

• For otitis media, sinusitis, lower respiratory tract infections, and more severe infections:
  • 45 mg/kg/day divided every 12 hours or 40 mg/kg/day divided every 8 hours 2
• For less severe infections:
  • 25 mg/kg/day divided every 12 hours or 20 mg/kg/day divided every 8 hours 2
• The twice-daily regimen is preferred as it is associated with significantly less diarrhea 2

Patients Weighing ≥40 kg

• Should be dosed according to adult recommendations 2
• The 250 mg/125 mg tablets should not be used until the child weighs at least 40 kg due to different amoxicillin to clavulanic acid ratios 2

High-Dose Regimen

• High-dose amoxicillin-clavulanate is defined as 90 mg/kg/day of amoxicillin with 6.4 mg/kg/day of clavulanate in two divided doses for children 3
• This regimen is recommended for areas with high prevalence of penicillin-resistant Streptococcus pneumoniae (>10%) 1
• The high-dose formulation provides a 14:1 ratio of amoxicillin to clavulanate in an oral suspension 3
• This higher dose is particularly important for treating acute otitis media caused by penicillin-intermediate and -resistant S. pneumoniae 4

Specific Indications and Dosing

Acute Otitis Media

• For recurrent or persistent AOM after failure of amoxicillin alone, high-dose amoxicillin/clavulanate (90 mg/kg/day of amoxicillin component) is recommended 4, 5
• Treatment duration should be 10 days 2
• The high-dose formulation has shown similar tolerability to conventional twice-daily formulation (45/6.4 mg/kg/day) 4

Respiratory Tract Infections

• For β-lactamase producing H. influenzae, amoxicillin-clavulanate at 45 mg/kg/day in 3 doses or 90 mg/kg/day in 2 doses is recommended 3
• The standard pediatric dose of 40-45 mg/kg/day may be inadequate to effectively eradicate resistant S. pneumoniae, particularly during viral coinfection 6

Important Clinical Considerations

• Twice-daily dosing is associated with better compliance and less diarrhea than three-times-daily dosing 4
• A reduced-clavulanate formulation (80 mg amoxicillin/2.85 mg clavulanate/kg/day) may be associated with fewer side effects (particularly diaper dermatitis) without reducing clinical efficacy 7
• Serum levels of amoxicillin increase linearly with the dose, and the difference in the incidence of adverse effects between lower and higher doses is generally negligible 3
• Common adverse effects include diarrhea, nausea, vomiting, and rash 3

Dosage Adjustments

• Patients with impaired renal function generally do not require a reduction in dose unless the impairment is severe 2
• For children with glomerular filtration rate <30 mL/min, dosage adjustment is necessary 2

By following these dosing guidelines, clinicians can optimize treatment outcomes while minimizing adverse effects in pediatric patients requiring amoxicillin-clavulanate therapy.