What is the recommended dose of ceftriaxone (Ceftriaxone) for a 1-year-old child weighing 9kg?

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Ceftriaxone Dosing for 1-Year-Old Child (9kg)

For a 1-year-old child weighing 9kg, administer ceftriaxone 50-75 mg/kg/day (450-675 mg/day) for most infections, given as a single daily dose or divided every 12 hours, with the specific dose depending on infection severity. 1, 2

Standard Dosing Algorithm by Infection Severity

For Less Severe Infections (skin/soft tissue, uncomplicated pneumonia):

  • Dose: 50-75 mg/kg/day = 450-675 mg/day 1, 2
  • Can be given as single daily dose or divided every 12 hours 1, 2
  • Maximum daily dose should not exceed 2 grams 2

For Severe Infections (severe pneumonia, sepsis, complicated infections):

  • Dose: 50-100 mg/kg/day = 450-900 mg/day 1, 3
  • Divided every 12 hours is preferred for severe infections 1
  • For severe sepsis specifically, use the higher end: 80-100 mg/kg/day (720-900 mg/day) 1

For Meningitis or CNS Infections:

  • Dose: 100 mg/kg/day = 900 mg/day 1, 2
  • Divided every 12 hours or given once daily 1, 2
  • Maximum 4 grams daily 1, 2

Administration Considerations

Route and Infusion Time:

  • Intravenous administration should be given over 30 minutes for children (60 minutes only for neonates) 2
  • Intramuscular injection is painful and should be injected deep into large muscle mass 1

Practical Dosing Example for This 9kg Child:

  • Moderate infection: 450 mg once daily or 225 mg every 12 hours 1, 2
  • Severe infection: 720-900 mg divided every 12 hours (360-450 mg per dose) 1
  • Meningitis: 900 mg divided every 12 hours (450 mg per dose) 1, 2

Critical Pitfalls to Avoid

  • Do not use the lower dosing range (50 mg/kg/day) for severe sepsis—this is inadequate for critically ill patients 1
  • Do not use ceftriaxone in hyperbilirubinemic infants due to risk of bilirubin encephalopathy 1
  • Do not mix with calcium-containing solutions (Ringer's, Hartmann's) as particulate formation can occur 2
  • For penicillin-resistant Streptococcus pneumoniae (MIC ≥4.0 μg/mL), must use 100 mg/kg/day 3

Special Pathogen Considerations

  • If staphylococcal infection suspected, add flucloxacillin 50 mg/kg every 6 hours plus gentamicin 1
  • If Listeria is a concern, add ampicillin 50 mg/kg every 6 hours 1
  • Ceftriaxone has no activity against Chlamydia trachomatis—add appropriate coverage if suspected 2

References

Guideline

Pediatric Dosing of Ceftriaxone

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Ceftriaxone Pediatric Dosage Recommendations

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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