What is the recommended dose of ceftriaxone (Ceftriaxone) for a patient weighing 4 kg?

Ceftriaxone Dosing for a 4 kg Patient

For a 4 kg pediatric patient, the recommended dose of ceftriaxone is 50 mg/kg/day, which equals 200 mg daily, given as a single dose or divided every 12-24 hours depending on the indication. 1, 2

General Dosing Guidelines

• For less severe infections, administer 50-75 mg/kg/day (200-300 mg for a 4 kg patient) given once daily or divided every 12-24 hours 1
• For severe infections including pneumonia, administer 50-100 mg/kg/day (200-400 mg for a 4 kg patient) given once daily or divided every 12-24 hours 1
• For bacterial meningitis, administer 100 mg/kg/day (400 mg for a 4 kg patient) divided every 12-24 hours (maximum 4 g daily) 1, 3

Administration Considerations

• Intravenous doses should be administered over 60 minutes in neonates to reduce the risk of bilirubin encephalopathy 2
• For older infants, administer intravenously by infusion over a period of 30 minutes 2
• Concentrations between 10 mg/mL and 40 mg/mL are recommended for IV administration 2

Special Considerations

• Ceftriaxone is contraindicated in hyperbilirubinemic neonates and premature neonates 2
• Ceftriaxone is contraindicated in neonates (≤28 days) if they require treatment with calcium-containing IV solutions due to risk of precipitation 2
• For neonates with postnatal age >7 days and >2000 g, the dose of ceftriaxone is 50-75 mg/kg/day given every 24 hours 1

Indication-Specific Dosing

• For skin and skin structure infections: 50-75 mg/kg/day given once daily or divided twice daily (total daily dose should not exceed 2 grams) 2
• For acute bacterial otitis media: a single intramuscular dose of 50 mg/kg (200 mg for a 4 kg patient) 2
• For serious miscellaneous infections other than meningitis: 50-75 mg/kg/day divided every 12 hours 2
• For gram-negative enteric bacilli infections: 100 mg/kg/day divided every 12 hours or 80 mg/kg/day every 24 hours (up to 4 g daily) 3, 1

Pharmacokinetic Considerations

• Ceftriaxone exhibits an exceptionally long elimination half-life (5.8 to 8.7 hours in adults, approximately 4.2 hours in pediatric patients) 4, 5
• Recent pharmacokinetic studies suggest that for critically ill children, a twice-daily dosing regimen of 50 mg/kg (100 mg twice daily for a 4 kg patient) may provide better target attainment for less susceptible pathogens 6, 7
• Once-daily dosing at 50 mg/kg has been shown to be effective for most non-meningitic bacterial infections in children 8

Monitoring

• No dosage adjustment is necessary for patients with impairment of renal or hepatic function up to 2 grams per day, unless there is severe impairment 2
• For patients on dialysis, plasma concentrations of ceftriaxone should be monitored as elimination rate may be significantly reduced 4