What is the recommended dosage of Ceftriaxone (Ceftriaxone) for an 11.8 kg child?

Ceftriaxone Dosing for an 11.8 kg Child

For an 11.8 kg child, order ceftriaxone 50-75 mg/kg/day (590-885 mg/day) given once daily or divided every 12 hours for most infections, or 100 mg/kg/day (1180 mg/day) for severe infections like meningitis or pneumococcal pneumonia with penicillin resistance. 1, 2

Standard Dosing Algorithm

For mild to moderate infections:

• Dose: 50-75 mg/kg/day (590-885 mg for this 11.8 kg child) 1, 2
• Can be given as a single daily dose or divided every 12 hours 1, 2
• Maximum daily dose should not exceed 2 grams for non-meningitis infections 2

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

• Dose: 50-100 mg/kg/day (590-1180 mg for this 11.8 kg child) 3, 1, 2
• Typically given once daily or divided every 12-24 hours 3, 1

For meningitis:

• Initial dose: 100 mg/kg (1180 mg for this 11.8 kg child), not to exceed 4 grams 2
• Maintenance: 100 mg/kg/day (1180 mg/day), given once daily or divided every 12 hours 1, 2
• Duration: 7-14 days 2

Pathogen-Specific Considerations

For Streptococcus pneumoniae with penicillin resistance (MIC ≥4.0 μg/mL):

• Use 100 mg/kg/day (1180 mg for this child) divided every 12-24 hours 3, 4
• This higher dose is critical for adequate CNS penetration and treatment of resistant strains 3

For community-acquired pneumonia:

• Dose: 50-100 mg/kg/day (590-1180 mg for this child) 3, 1
• The higher end (100 mg/kg/day) is preferred for hospitalized children or when high-level penicillin resistance is documented 3

For Group A Streptococcus or less resistant S. pneumoniae:

• Dose: 50-100 mg/kg/day (590-1180 mg for this child) 3, 4

Administration Guidelines

Route selection:

• Intravenous administration: Infuse over 30 minutes at concentrations of 10-40 mg/mL 2
• Intramuscular administration: Inject deep into large muscle mass; counsel family that IM injection is painful 3, 5

Critical safety considerations:

• Never use calcium-containing diluents (Ringer's solution, Hartmann's solution) as particulate formation can occur 5, 2
• Use sterile water, 0.9% sodium chloride, or 5% dextrose for reconstitution 2

Practical Ordering Examples

For this 11.8 kg child with community-acquired pneumonia (moderate severity):

• Order: Ceftriaxone 700 mg IV once daily (approximately 60 mg/kg/day) 3, 1

For this 11.8 kg child with suspected meningitis:

• Order: Ceftriaxone 1200 mg IV divided every 12 hours (600 mg every 12 hours = 100 mg/kg/day) 1, 2

For this 11.8 kg child with severe sepsis:

• Order: Ceftriaxone 1000 mg IV once daily (approximately 85 mg/kg/day) 1

Common Pitfalls to Avoid

• Do not underdose severe infections: For life-threatening infections, empyema, or documented resistant pneumococcus, always use 100 mg/kg/day, not the lower 50 mg/kg/day range 3, 1
• Do not use in hyperbilirubinemic neonates: Ceftriaxone is contraindicated in jaundiced neonates due to risk of bilirubin encephalopathy 1
• Do not mix with calcium-containing solutions: This can cause fatal precipitation 5, 2
• Do not exceed maximum doses: Even with weight-based dosing, do not exceed 4 grams daily for meningitis or 2 grams daily for other infections 2