Cefazolin IV Dosing Guidelines
The recommended IV dosing for cefazolin in adults is 1-2 grams every 8 hours for most moderate to severe infections, with dose adjustments required for renal impairment. 1
Adult Dosing Recommendations
Standard Dosing by Indication
- Moderate to severe infections: 500 mg to 1 gram every 6 to 8 hours 1
- Mild infections caused by susceptible gram-positive cocci: 250 mg to 500 mg every 8 hours 1
- Severe, life-threatening infections (e.g., endocarditis, septicemia): 1 gram to 1.5 grams every 6 hours 1
- Non-purulent skin and soft tissue infections: 1 gram every 8 hours IV 2
Surgical Prophylaxis
- Pre-operative dose: 1 gram IV administered 30 minutes to 1 hour prior to surgery 1
- For lengthy procedures (≥2 hours): Additional 500 mg to 1 gram IV during surgery 1
- Post-operative dosing: 500 mg to 1 gram IV every 6 to 8 hours for 24 hours 1
- Special cases (e.g., open-heart surgery, prosthetic arthroplasty): May continue prophylaxis for 3 to 5 days 1
Pediatric Dosing
- General infections: 25-50 mg/kg/day divided into 3 or 4 equal doses 1
- Severe infections: May increase up to 100 mg/kg/day 1
- Non-purulent skin and soft tissue infections: 33 mg/kg/dose 2
- Endocarditis: 100 mg/kg/day IV divided every 8 hours up to 12 g daily 2
Renal Dosage Adjustments for Adults
| Creatinine Clearance | Serum Creatinine | Dosing Recommendation |
|---|---|---|
| ≥55 mL/min | ≤1.5 mg% | Full dose |
| 35-54 mL/min | 1.6-3.0 mg% | Full dose, at least 8-hour intervals |
| 11-34 mL/min | 3.1-4.5 mg% | 1/2 usual dose every 12 hours |
| ≤10 mL/min | ≥4.6 mg% | 1/2 usual dose every 18-24 hours |
Note: All reduced dosage recommendations apply after an initial loading dose appropriate to the severity of the infection. 1
Renal Dosage Adjustments for Pediatric Patients
- Mild to moderate impairment (CrCl 70-40 mL/min): 60% of normal daily dose every 12 hours 1
- Moderate impairment (CrCl 40-20 mL/min): 25% of normal daily dose every 12 hours 1
- Severe impairment (CrCl 20-5 mL/min): 10% of normal daily dose every 24 hours 1
Administration Guidelines
IV Administration Methods
- Direct (bolus) injection: Reconstitute with approximately 5 mL Sterile Water for Injection. Inject slowly over 3-5 minutes 1
- Intermittent or continuous infusion: Dilute in 50-100 mL of compatible solution 1
Special Considerations
Tissue Penetration
- Cefazolin demonstrates good tissue penetration with a mean tissue penetration ratio of 1.06 in lower limb infections 3
- This favorable penetration supports its use in skin and soft tissue infections
Duration of Therapy
- For surgical prophylaxis: Limited to the operative period, sometimes 24 hours, exceptionally 48 hours and never beyond 2
- For treatment of infections: Duration depends on the specific infection being treated
Common Pitfalls and Caveats
Timing of preoperative dose: Critical to administer 30-60 minutes before surgical incision to ensure adequate tissue levels at the time of incision 1
Reinjection during lengthy procedures: For surgeries lasting >4 hours, administer an additional 1g dose to maintain therapeutic levels 1
Renal function monitoring: Regular assessment of renal function is essential, especially in critically ill patients, as dosage adjustments are required for declining renal function 1
Not recommended for premature infants and neonates: Safety not established in these populations 1
Maximum daily dose: In rare instances, doses up to 12 grams per day have been used for severe infections 1
By following these evidence-based dosing recommendations and considering patient-specific factors like renal function, cefazolin can be effectively and safely administered for a variety of infectious indications.