Dosing Recommendations for Second‑Generation Cephalosporins
Adult Dosing Regimens
- For routine surgical prophylaxis and most adult infections, administer cefazolin 1 g IV every 8 h, cefuroxime 500 mg PO every 12 h (or 1.5 g IV every 8–12 h), cefoxitin 1–2 g IV every 8 h, and cefprozil 500 mg PO every 12 h. 1
- In urologic surgical prophylaxis, cefazolin 1 g IV every 8 h is the standard second‑generation cephalosporin option, despite its classification as a first‑generation agent. 1
- For prolonged surgical procedures, intra‑operative redosing of short‑half‑life agents (e.g., cefazolin, cefuroxime) should occur earlier than the standard interval to maintain therapeutic levels. 1
Adult Specific Indications
- Mild‑to‑moderate intra‑abdominal infections should be treated with cefuroxime, ceftriaxone, or cefotaxime plus metronidazole as combination therapy. 2
Pediatric Dosing Overview
- For febrile infants and children with bacterial infections, ceftriaxone 50–100 mg/kg/day IV is the most frequently recommended second/third‑generation cephalosporin. 3
Age‑Stratified Pediatric Regimens
| Age Group | Infection Focus | Recommended Regimen (dose & route) |
|---|---|---|
| Neonates & young infants (8–21 days) | UTI or no identified focus | Ampicillin 150 mg/kg/day IV q8 h plus either ceftazidime 150 mg/kg/day IV q8 h or gentamicin 4 mg/kg IV once daily. |
| Neonates & young infants (8–21 days) | Bacterial meningitis | Ampicillin 300 mg/kg/day IV q6 h plus ceftazidime 150 mg/kg/day IV q8 h. |
| Infants (22–28 days) | UTI or no identified focus | Ceftriaxone 50 mg/kg IV once daily. |
| Infants (22–28 days) | Bacterial meningitis | Ampicillin 300 mg/kg/day IV q6 h plus ceftazidime 150 mg/kg/day IV q8 h. |
| Infants & children (29–60 days) – UTI | – | Ceftriaxone 50 mg/kg IV once daily or oral cephalexin 50–100 mg/kg/day divided q6 h or cefixime 8 mg/kg once daily (for >28 days). |
| Infants & children (29–60 days) – No identified focus | – | Ceftriaxone 50 mg/kg IV once daily. |
| Infants & children (29–60 days) – Bacterial meningitis | – | Ceftriaxone 100 mg/kg/day IV once daily or divided q12 h or ceftazidime 150 mg/kg/day IV q8 h plus vancomycin 60 mg/kg/day IV q8 h. |
*All regimens above are derived from pediatric infectious disease guidelines. 3
Pediatric Specific Infections
- For mild‑to‑moderate intra‑abdominal infections in children, use cefotaxime, ceftriaxone, ceftazidime, or cefepime plus metronidazole. 2
- For community‑acquired pneumonia in children, prescribe oral cefuroxime 30 mg/kg/day divided twice daily for a 10‑day course. 4
Dosing for Multidrug‑Resistant Organism (MDRO) Infections
Cefepime:
- Neonates < 36 weeks gestational age – 30 mg/kg IV every 12 h.
- Neonates ≥ 36 weeks gestational age – 50 mg/kg IV every 12 h.
- Children – 50 mg/kg IV every 8 h (maximum 2000 mg per dose).
Ceftazidime:
- Neonates < 32 weeks gestational age and < 14 days old – 50 mg/kg IV every 12 h.
- Neonates ≥ 32 weeks gestational age and > 7 days old – 50 mg/kg IV every 8 h.
- Children with serious Pseudomonas infections – 200–300 mg/kg/day IV divided into three doses (maximum 12 g per day).
*These MDRO‑specific dosing recommendations are based on recent antimicrobial stewardship guidelines. 5