What is the recommended dose of Monocef (Ceftriaxone) for a 38kg child?

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Monocef (Ceftriaxone) Dosing for a 38 kg Child

For a 38 kg child, the recommended dose of Monocef (Ceftriaxone) is 50-75 mg/kg/day given once daily or divided every 12-24 hours, which equals 1900-2850 mg/day, not to exceed 2 grams per day for most infections. 1

Dosing Based on Indication

  • For less severe infections: 50-75 mg/kg/day given once daily or divided every 12-24 hours (1900-2850 mg/day), not to exceed 2 grams daily 2, 1
  • For severe infections including pneumonia: 50-100 mg/kg/day given once daily or divided every 12-24 hours (1900-3800 mg/day), not to exceed 2 grams daily for most infections 2
  • For bacterial meningitis: 100 mg/kg/day divided every 12-24 hours (3800 mg/day), not to exceed 4 grams daily 2, 1
  • For skin and skin structure infections: 50-75 mg/kg/day given once daily or divided twice a day (1900-2850 mg/day), not to exceed 2 grams daily 1
  • For acute bacterial otitis media: A single intramuscular dose of 50 mg/kg (1900 mg), not to exceed 1 gram 1

Pathogen-Specific Dosing

  • For Streptococcus pneumoniae with penicillin MIC <2.0 μg/mL: 50-100 mg/kg/day every 12-24 hours (1900-3800 mg/day) 3
  • For penicillin-resistant Streptococcus pneumoniae (MIC ≥4.0 μg/mL): 100 mg/kg/day every 12-24 hours (3800 mg/day) 3
  • For Group A Streptococcus: 50-100 mg/kg/day every 12-24 hours (1900-3800 mg/day) 3
  • For Haemophilus influenzae (β-lactamase producing): 50-100 mg/kg/day every 12-24 hours (1900-3800 mg/day) 3

Administration Guidelines

  • Intravenous doses should be administered over 30 minutes 1
  • For intramuscular administration, reconstitute with appropriate diluent and inject well within the body of a relatively large muscle 1
  • Duration of therapy is typically 4-14 days; for complicated infections, longer therapy may be required 1
  • When treating Streptococcus pyogenes infections, therapy should be continued for at least 10 days 1

Important Considerations

  • No dosage adjustment is necessary for patients with impairment of renal or hepatic function 1
  • Do not use diluents containing calcium, such as Ringer's solution or Hartmann's solution, to reconstitute ceftriaxone 1
  • Once-daily administration of ceftriaxone at 50-80 mg/kg has been shown to be effective for serious bacterial infections in children with a clinical cure rate of 94% 4
  • For patients with an estimated glomerular filtration rate of >80 mL/min/1.73 m² or in areas with less-susceptible pathogens, a twice-daily dosing regimen of 50 mg/kg (1900 mg twice daily for this 38 kg child) may improve target attainment 5

Clinical Evidence Support

  • Studies have shown that ceftriaxone trough levels with once-daily dosing of 50 mg/kg exceeded the MIC of most infecting organisms, supporting the efficacy of once-daily dosing 6
  • Single-dose pharmacokinetic studies in pediatric patients with CNS infections have demonstrated adequate CSF penetration of ceftriaxone, with concentrations exceeding the MICs of causative bacteria by hundreds to thousands of times 7

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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