What is the recommended dose of amoxicillin-clavulanate (amoxicillin-clavulanate) for pediatric patients?

Amoxicillin-Clavulanate Dosing in Pediatric Patients

For most pediatric respiratory and soft tissue infections, use high-dose amoxicillin-clavulanate at 90 mg/kg/day of the amoxicillin component with 6.4 mg/kg/day of clavulanate, divided into 2 doses daily, with a maximum of 4000 mg/day of amoxicillin. 1

Standard Dosing Algorithm by Age and Weight

Infants and Young Children (Weight-Based Dosing)

For children under 40 kg, always calculate doses based on weight:

• Infants <1 year (1-12 months): 2.5 ml of 125/31 suspension three times daily 1
• Children 1-6 years: 5 ml of 125/31 suspension three times daily 1
• Children 7-12 years: 5 ml of 250/62 suspension three times daily 1

Critical consideration: These age-based volumes provide standard dosing (approximately 45 mg/kg/day), which is inadequate for resistant organisms. 1

High-Dose Regimen (Preferred for Most Infections)

The high-dose regimen of 90 mg/kg/day amoxicillin with 6.4 mg/kg/day clavulanate in 2 divided doses is strongly recommended as first-line therapy for: 1, 2

• Children <2 years of age 1, 2
• Daycare attendance 1, 3
• Recent antibiotic use within 30 days 1, 3
• Incomplete Haemophilus influenzae type b vaccination 1, 2
• Geographic areas with >10% penicillin-resistant Streptococcus pneumoniae 1, 3
• Moderate to severe illness 1
• Concurrent purulent otitis media 1

This high-dose formulation provides a 14:1 ratio of amoxicillin to clavulanate, which causes significantly less diarrhea than other formulations while maintaining superior efficacy against resistant pathogens. 1, 2

Children ≥40 kg

For children weighing 40 kg or more, use adult dosing regimens rather than pediatric weight-based calculations: 3

• Standard dose: 500 mg/125 mg three times daily 3
• High-dose (for resistant organisms): 875 mg/125 mg twice daily or 2000 mg/125 mg twice daily 3

Indication-Specific Dosing

Acute Otitis Media (AOM)

High-dose amoxicillin-clavulanate (90 mg/kg/day divided BID) is the treatment of choice for children under 2 years with AOM, with treatment duration of 8-10 days. 1, 2

• The high-dose formulation achieves middle ear fluid concentrations adequate to overcome penicillin-resistant S. pneumoniae with MICs of 2-4 mg/L 1
• Clinical response rates of 76-95% have been documented 1
• This regimen is specifically indicated for severe AOM, bilateral AOM in children 6-23 months, or recent amoxicillin use 1

Community-Acquired Pneumonia

For presumed bacterial pneumonia in children <5 years requiring outpatient treatment: 1

• First-line: Amoxicillin alone at 80-100 mg/kg/day in 3 divided doses 1
• Add clavulanate (90 mg/kg/day amoxicillin component in 2 doses) if: 1
  • Incomplete H. influenzae type b vaccination
  • Concurrent purulent otitis media
  • Treatment failure with amoxicillin alone
• Duration: 10 days 1, 2

Acute Bacterial Rhinosinusitis (ABRS)

High-dose amoxicillin-clavulanate (90 mg/kg/day divided BID) is strongly recommended as first-line therapy for children with ABRS, with treatment duration of 10-14 days. 1, 2

Intravenous Dosing

For severe infections requiring IV therapy: 1

• All pediatric ages: 30 mg/kg three times daily IV 1
• Switch to oral formulation as soon as clinically appropriate 3

Special Populations

Neonates and Infants <3 Months

For infants under 12 weeks of age: 4

• Maximum dose: 30 mg/kg/day divided every 12 hours 4
• This reduced dosing is due to incompletely developed renal function 4
• No specific dosing recommendations exist for infants with impaired renal function 4

Renal Impairment (Children >3 Months and >40 kg)

For severe renal impairment: 4

• GFR 10-30 mL/min: 500 mg or 250 mg every 12 hours 4
• GFR <10 mL/min: 500 mg or 250 mg every 24 hours 4
• Hemodialysis: 500 mg or 250 mg every 24 hours, with additional dose during and at end of dialysis 4
• Do NOT use 875 mg dose if GFR <30 mL/min 4

Treatment Duration by Indication

• Acute otitis media: 8-10 days (children <2 years), 10 days (older children) 1, 2
• Bacterial pneumonia: 10 days 1, 2
• Acute bacterial rhinosinusitis: 10-14 days 1, 2
• Most respiratory infections: 7-10 days 1
• Continue treatment 48-72 hours beyond symptom resolution 4

Reassessment Protocol

If no improvement or worsening after 72 hours: 1, 2

• Re-evaluate the diagnosis clinically and consider imaging 1
• Consider atypical pathogens (Mycoplasma, Chlamydia) 1
• Evaluate for complications (mastoiditis, intracranial extension, empyema) 1
• Consider switching antibiotics or obtaining cultures 3

Critical Pitfalls to Avoid

Underdosing Errors

Using standard doses (45 mg/kg/day) when high-dose therapy is indicated leads to inevitable treatment failure with resistant organisms and promotes antimicrobial resistance. 1

• Subtherapeutic doses fail to achieve adequate serum and tissue concentrations even against susceptible organisms 1
• Treatment failure rates of 20-25% occur when standard-dose therapy is used in the presence of risk factors for resistance 3

Formulation Confusion

Always verify the suspension concentration (125/31 vs 250/62) before calculating volume to avoid dosing errors. 1, 2

• The 14:1 ratio formulation (90/6.4 mg/kg/day) is specifically designed to minimize diarrhea 1, 2
• Using incorrect ratios (such as 7:1 or 4:1 formulations) results in excessive clavulanate and significantly more gastrointestinal side effects 1

Inappropriate Antibiotic Use

Most upper respiratory tract infections are viral and do not benefit from antibiotics. 1

• Before prescribing, ensure the child meets criteria for bacterial infection (persistent symptoms >10 days, severe symptoms, or "double sickening") 1
• Prescribing antibiotics for viral URTIs increases adverse effects without benefit 1

Adverse Effects and Tolerability

Common adverse effects include: 1, 2

• Diarrhea (17-26% with high-dose formulation) 5
• Diaper dermatitis (21-33%) 1, 5
• Nausea and vomiting 1
• Rash 1

The 14:1 ratio high-dose formulation causes significantly less diarrhea than standard 7:1 formulations while maintaining superior efficacy. 1, 2 Recent evidence suggests even lower clavulanate concentrations (80 mg/kg amoxicillin with 2.85 mg/kg clavulanate) may reduce side effects further without compromising efficacy 5, though this is not yet standard practice.

Administration Guidelines

• Take at the start of meals to minimize gastrointestinal intolerance 4
• Shake oral suspension well before each use 4
• Refrigeration is preferable but not required 4
• Discard unused reconstituted suspension after 14 days 4