What is the recommended dosing of Monocef (ceftriaxone) for children?

Monocef (Ceftriaxone) Pediatric Dosing

For most pediatric infections, ceftriaxone should be dosed at 50-75 mg/kg/day given once daily or divided every 12 hours, with higher doses of 100 mg/kg/day reserved for meningitis and severe infections, not exceeding 4 grams daily. 1, 2

Age-Specific Dosing for Neonates

Neonatal dosing requires special attention to age and weight:

• Neonates ≤7 days old: 50 mg/kg/day given every 24 hours 1
• Neonates >7 days and ≤2000 g: 50 mg/kg/day given every 24 hours 1
• Neonates >7 days and >2000 g: 50-75 mg/kg/day given every 24 hours 1

Critical contraindication: Never use ceftriaxone in hyperbilirubinemic neonates due to risk of bilirubin encephalopathy 1, 2

Infection-Specific Dosing for Children

Severe Infections Requiring Higher Doses

• Bacterial meningitis: 100 mg/kg/day divided every 12-24 hours (maximum 4 g daily) 1, 2
• Pneumococcal pneumonia with penicillin resistance (MIC ≥4.0 μg/mL): 100 mg/kg/day every 12-24 hours 1, 3
• Gram-negative enteric bacilli infections: 100 mg/kg/day divided every 12 hours or 80 mg/kg/day every 24 hours (maximum 4 g daily) 1
• Infective endocarditis (HACEK organisms): 100 mg/kg/day IV/IM once daily for 4 weeks (native valve) or 6 weeks (prosthetic valve) 1

Moderate to Severe Infections

• Community-acquired pneumonia: 50-100 mg/kg/day given once daily or divided every 12-24 hours 1, 3
• Skin and skin structure infections: 50-75 mg/kg/day given once daily or divided twice daily (maximum 2 g daily) 1, 2
• Complicated intra-abdominal infections: 50-75 mg/kg/day given every 12-24 hours 1
• Sepsis: 50-75 mg/kg/day given every 12-24 hours 1

Single-Dose Regimens

• Acute bacterial otitis media: Single IM dose of 50 mg/kg (maximum 1 gram) 2
• Uncomplicated gonococcal infections (<45 kg): 125 mg IM single dose 1
• Gonococcal conjunctivitis (≤45 kg): 25-50 mg/kg IV or IM single dose (maximum 250 mg) 1

Extended Treatment Regimens

• Gonococcal bacteremia or arthritis: 50 mg/kg/day given daily for 7 days 1

Administration Guidelines

Route and timing considerations:

• Intravenous administration: Infuse over 30 minutes in children; 60 minutes in neonates to reduce bilirubin encephalopathy risk 2
• Intramuscular administration: Inject deep into large muscle mass; counsel patients about significant pain associated with IM injection 1, 4
• Concentration for IV: 10-40 mg/mL recommended, though lower concentrations may be used 2

Critical safety warning: Never use calcium-containing diluents (Ringer's solution, Hartmann's solution) as particulate formation can occur 4, 2

Maximum Dose Limitations

Pediatric doses should never exceed adult maximum doses of 4 grams daily, regardless of calculated weight-based dosing. 1, 2

Pathogen-Specific Considerations

When treating specific pathogens with known susceptibility:

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

Common Pitfalls to Avoid

• Do not use in jaundiced neonates - absolute contraindication due to displacement of bilirubin from albumin 1
• Avoid calcium-containing solutions - can cause fatal precipitation 4, 2
• Do not mix with other antimicrobials - administer sequentially with thorough line flushing 2
• Ensure adequate infusion time in neonates - 60 minutes required, not 30 minutes 2
• Consider twice-daily dosing for critically ill children with estimated GFR >80 mL/min/1.73 m² or when treating less-susceptible pathogens (MIC ≥0.5 mg/L) to improve target attainment 5