Ceftriaxone Dosing for a 5-Year-Old Boy
For a 5-year-old child, administer ceftriaxone 50-75 mg/kg/day for most infections, with the dose given once daily or divided every 12 hours, not to exceed 2 grams daily. 1
Standard Dosing by Infection Type
Non-Meningitis Infections
- For skin and soft tissue infections: Give 50-75 mg/kg once daily or divided every 12 hours (maximum 2 grams/day) 1
- For serious miscellaneous infections (pneumonia, sepsis, complicated intra-abdominal infections): Use 50-75 mg/kg/day divided every 12 hours (maximum 2 grams/day) 1
- For acute bacterial otitis media: A single intramuscular dose of 50 mg/kg (not to exceed 1 gram) is recommended 1
Meningitis
- For bacterial meningitis: Use 100 mg/kg/day (maximum 4 grams/day), given once daily or divided every 12 hours 1
- The initial therapeutic dose should be 100 mg/kg, then continue with 100 mg/kg/day for 7-14 days 1
- Recent pharmacokinetic data supports once-daily dosing (100 mg/kg) over twice-daily dosing (50 mg/kg BD) for meningitis, as it achieves better CSF target attainment in the first 24 hours 2
Practical Dosing Example
For a typical 5-year-old weighing approximately 18-20 kg:
- Standard infections: 900-1500 mg once daily or 450-750 mg every 12 hours 1
- Meningitis: 1800-2000 mg once daily or 900-1000 mg every 12 hours 1
Administration Guidelines
- Intravenous administration: Infuse over 30 minutes for children (60 minutes only required for neonates) 1
- Intramuscular administration: Inject deep into a large muscle mass; this route is painful and patients should be counseled accordingly 3
- Do not use calcium-containing diluents (Ringer's solution, Hartmann's solution) as precipitation can occur 1
Important Clinical Considerations
- The once-daily dosing advantage of ceftriaxone makes it particularly useful for outpatient parenteral antibiotic therapy 4
- For critically ill children with normal renal function (eGFR >80 mL/min/1.73 m²) or infections with less susceptible pathogens (MIC ≥0.5 mg/L), consider twice-daily dosing of 50 mg/kg to improve target attainment 5
- Ceftriaxone has no activity against Chlamydia trachomatis; add appropriate antichlamydial coverage if suspected 1
- No dosage adjustment is necessary for renal or hepatic impairment in children 1
Common Pitfalls to Avoid
- Do not exceed maximum daily doses: 2 grams for non-meningitis infections, 4 grams for meningitis 1
- Avoid in hyperbilirubinemic neonates (not applicable to a 5-year-old, but important to remember) 6, 3
- For Staphylococcus aureus meningitis, standard ceftriaxone dosing may be inadequate; consider alternative therapy 2