Recommended Dosage of Cefazolin for Pediatric Patients
For pediatric patients, the recommended dose of cefazolin is 150 mg/kg/day divided every 8 hours for parenteral (IV) administration. 1
Dosing by Age Group and Clinical Scenario
Children > 1 month of age
- 75 mg/kg every 8 hours (150 mg/kg/day divided into 3 doses) for parenteral therapy 1
- For methicillin-susceptible Staphylococcus aureus infections, this is the preferred parenteral regimen 1
Standard Pediatric Dosing
- For most mild to moderately severe infections: 25-50 mg/kg/day divided into 3 or 4 equal doses 2
- For severe infections: total daily dosage may be increased to 100 mg/kg/day 2
Weight-Based Dosing Guide
25 mg/kg/day divided into 3 doses (approximately every 8 hours):
- 10 kg child: 40 mg per dose
- 20 kg child: 75 mg per dose
- 30 kg child: 115 mg per dose
- 40 kg child: 150 mg per dose
- 50 kg child: 190 mg per dose 2
50 mg/kg/day divided into 3 doses (approximately every 8 hours):
- 10 kg child: 75 mg per dose
- 20 kg child: 150 mg per dose
- 30 kg child: 225 mg per dose
- 40 kg child: 300 mg per dose
- 50 kg child: 375 mg per dose 2
Dosing in Special Populations
Renal Impairment
- Mild to moderate renal impairment (creatinine clearance 70-40 mL/min): 60% of normal daily dose given every 12 hours 2
- Moderate impairment (creatinine clearance 40-20 mL/min): 25% of normal daily dose given every 12 hours 2
- Severe renal impairment (creatinine clearance 20-5 mL/min): 10% of normal daily dose every 24 hours 2
Perioperative Prophylaxis
- Recent research suggests that standard dosing regimens may be suboptimal during cardiac surgery with cardiopulmonary bypass 3
- For surgical prophylaxis in children undergoing cardiac surgery with cardiopulmonary bypass, continuous infusion may be more effective than intermittent dosing 3
Important Clinical Considerations
- Safety has not been established for premature infants and neonates, so cefazolin is not recommended in these populations 2
- For methicillin-susceptible Staphylococcus aureus infections, cefazolin is preferred over other agents 1
- When transitioning to oral therapy, cephalexin at 75-100 mg/kg/day in 3-4 doses is the preferred option 1
Potential Pitfalls and Caveats
- Ensure appropriate loading dose is given before maintenance dosing, especially in severe infections 2
- Reconstituted solutions should be used within 24 hours at room temperature or within 10 days if refrigerated 2
- For intramuscular administration, cefazolin should be injected into a large muscle mass to minimize pain at injection site 2
- Recent evidence suggests that higher doses with less frequent administration may be effective for some cephalosporins, but this approach has not been formally validated for cefazolin in pediatric patients 4, 5
Remember that while these dosing recommendations are based on current guidelines, the clinical response should be monitored carefully, particularly in severe infections or when treating resistant organisms.