What is the appropriate dosage of Augmentin (amoxicillin-clavulanate) for an 11-year-old?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: November 25, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Augmentin Dosing for an 11-Year-Old Child

For an 11-year-old child, the appropriate Augmentin dosage depends on the infection type and severity, but typically ranges from 45 mg/kg/day divided every 12 hours for mild-moderate infections to 90 mg/kg/day divided every 12 hours for severe infections or areas with high antibiotic resistance, with a maximum of 2000 mg per dose. 1, 2

Standard Dosing Framework

Weight-Based Calculation (Most Accurate)

The typical 11-year-old weighs approximately 35-40 kg, though individual weight should always be verified. 1

For mild to moderate infections:

  • 45 mg/kg/day of amoxicillin component divided every 12 hours 1, 2
  • For a 35 kg child: approximately 787.5 mg twice daily
  • For a 40 kg child: approximately 900 mg twice daily 3

For severe infections or high-resistance areas:

  • 90 mg/kg/day of amoxicillin component divided every 12 hours 1, 2
  • For a 35 kg child: approximately 1575 mg twice daily
  • For a 40 kg child: approximately 1800 mg twice daily 2
  • Maximum single dose: 2000 mg regardless of weight 2

Age-Based Dosing (When Weight Unknown)

For children aged 7-12 years, the standard recommendation is 5 mL of 250/62 suspension three times daily 2, though this provides lower total daily dosing than weight-based calculations and may be inadequate for resistant organisms.

Infection-Specific Recommendations

Respiratory Tract Infections

  • Community-acquired pneumonia: 90 mg/kg/day in 2 doses for 10 days 1, 2
  • Acute bacterial sinusitis: High-dose amoxicillin-clavulanate (90 mg/kg/day with 6.4 mg/kg/day clavulanate) if worsening after 72 hours on standard therapy 4
  • Mild respiratory infections: 45 mg/kg/day in 2 doses for 7-10 days 1

Skin and Soft Tissue Infections

  • Standard dosing: 45 mg/kg/day divided every 12 hours 3
  • Severe infections: 90 mg/kg/day divided every 12 hours 5
  • Duration: 7-10 days, extendable to 14 days based on clinical response 5

High-Dose Formulation Rationale

The high-dose regimen (90 mg/kg/day amoxicillin with 6.4 mg/kg/day clavulanate in a 14:1 ratio) is specifically indicated for: 2, 6

  • Age <2 years
  • Daycare attendance
  • Recent antibiotic use within past 30 days
  • Moderate to severe illness
  • Geographic areas with >10% penicillin-resistant S. pneumoniae 2

This formulation maintains plasma concentrations adequate to overcome intermediately resistant S. pneumoniae (MIC up to 4 mcg/mL) while causing less diarrhea than older formulations due to the optimized ratio. 2, 7

Critical Dosing Considerations

Renal Impairment

  • GFR 10-30 mL/min: 500 mg or 250 mg every 12 hours 3
  • GFR <10 mL/min: 500 mg or 250 mg every 24 hours 3
  • Hemodialysis: Additional dose during and after dialysis 3

Administration Guidelines

  • Take at the start of meals to minimize gastrointestinal intolerance 3
  • Shake oral suspension well before each use 3
  • Reconstituted suspension expires after 14 days; refrigeration preferred but not required 3

Treatment Duration

Minimum treatment duration: 48-72 hours beyond symptom resolution or bacterial eradication 3

Infection-specific durations:

  • Pneumonia: 10 days 1, 2
  • Sinusitis: 10-14 days 4
  • Skin infections: 7-10 days (up to 14 days for severe cases) 5
  • Streptococcus pyogenes infections: Minimum 10 days to prevent rheumatic fever 3

Common Pitfalls to Avoid

Underdosing is the most critical error - using standard doses when high-dose therapy is indicated leads to treatment failure with resistant organisms and promotes antimicrobial resistance. 2

Verify suspension concentration (125/31 vs 250/62) before calculating volume to avoid dosing errors. 2

Do not use 875 mg tablets in patients with GFR <30 mL/min - this formulation is contraindicated in severe renal impairment. 3

Ensure appropriate indication - most upper respiratory infections are viral and do not benefit from antibiotics; confirm bacterial infection criteria before prescribing. 2

Monitoring and Follow-Up

Children should demonstrate clinical improvement within 48-72 hours of appropriate antibiotic therapy. 1, 2

If no improvement occurs:

  • Reassess diagnosis
  • Consider resistant organisms
  • Evaluate for complications
  • Consider alternative therapy (clindamycin plus cefixime, linezolid plus cefixime, or levofloxacin) 4

Complete the full prescribed course even if symptoms improve before completion to prevent treatment failure and resistance development. 2

References

Guideline

Amoxicillin Dosing Guidelines for Pediatric Patients

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Amoxicillin-Clavulanate Dosing in Pediatric Patients

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Co-amoxiclav Dosage and Treatment for Pediatric Skin Infections

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.