What is the recommended dose of Amoxiclav (amoxicillin-clavulanate) for an 18-month-old pediatric patient?

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Amoxicillin-Clavulanate Dosing for an 18-Month-Old Child

For an 18-month-old child, the recommended dose of amoxicillin-clavulanate (Amoxiclav) is 5 ml of 125/31 suspension three times daily. 1

Dosing Guidelines Based on Age

  • For children aged 1-6 years, the appropriate dose of amoxicillin-clavulanate is 5 ml of 125/31 suspension three times daily 1
  • For children under 1 year, the dose would be 2.5 ml/kg of 125/31 suspension three times daily 1
  • For children over 6 years, the dose increases to 5 ml of 250/62 suspension three times daily 1

Dosing Based on Weight and Indication

  • For standard infections, the FDA recommends 25 mg/kg/day divided every 12 hours or 20 mg/kg/day divided every 8 hours for mild to moderate infections 2
  • For more severe infections, the FDA recommends 45 mg/kg/day divided every 12 hours or 40 mg/kg/day divided every 8 hours 2
  • For respiratory tract infections in areas with high pneumococcal resistance, higher dosing of 90 mg/kg/day may be warranted 3

Administration Guidelines

  • Amoxicillin-clavulanate should be taken at the start of a meal to minimize gastrointestinal intolerance 2
  • The oral suspension should be shaken well before using 2
  • Treatment should generally be continued for a minimum of 48 to 72 hours beyond the time that the patient becomes asymptomatic 2
  • For infections caused by Streptococcus pyogenes, treatment should continue for at least 10 days to prevent acute rheumatic fever 2

Potential Adverse Effects

  • The most common adverse effects include gastrointestinal disturbances such as diarrhea, which is more common with amoxicillin-clavulanate than with some other antibiotics 3
  • Rash, urticaria, and other hypersensitivity reactions may occur 3
  • Monitoring for signs of allergic reaction is important, especially with the first few doses 3

Special Considerations

  • If the child has renal impairment, dose adjustment may be necessary 2
  • After reconstitution, the oral suspension must be refrigerated and discarded after 14 days 2
  • For children who cannot take the medication directly, the suspension can be added to formula, milk, fruit juice, water, or cold drinks and should be taken immediately 2

Remember that appropriate dosing is essential for efficacy while minimizing the risk of adverse effects and antimicrobial resistance. The 5 ml of 125/31 suspension three times daily regimen provides adequate coverage for most common pediatric infections in an 18-month-old child.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Amoxicillin Dosing Guidelines for Pediatric Patients

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.

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