What is the use of Cefazolin (Ancef)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: May 18, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Cefazolin is the recommended antibiotic for surgical prophylaxis in most procedures, including orthopedic, cardiac, and gastrointestinal surgeries, due to its effectiveness against gram-positive organisms and some gram-negative bacteria, as well as its excellent tissue penetration, particularly in bone 1.

Key Points

  • The typical adult dose of cefazolin for surgical prophylaxis is a single 2-gram dose (3 grams for patients >120 kg) administered within 60 minutes before incision, with redosing recommended for procedures lasting longer than 4 hours 1.
  • Cefazolin is particularly effective against methicillin-sensitive Staphylococcus aureus and many streptococci, as well as some gram-negative bacteria, making it a first-line option for surgical prophylaxis in many cases 1.
  • Common side effects of cefazolin include gastrointestinal disturbances, rash, and allergic reactions, with cross-reactivity with penicillin allergies occurring in approximately 5-10% of patients 1.
  • Cefazolin has poor central nervous system penetration, limiting its use for meningitis, but its excellent tissue penetration in bone makes it ideal for orthopedic procedures 1.

Surgical Prophylaxis Guidelines

  • The Australian Therapeutic Guidelines (2019) recommend cefazolin as the first-choice option for most surgical procedures, including gastrointestinal, cardiac, and orthopedic surgeries 1.
  • The French Society of Anesthesia and Intensive Care Medicine (2018) also recommends cefazolin as the first-choice option for most surgical procedures, including neurosurgery, cardiac and vascular surgery, and orthopedic surgery 1.
  • The American Society of Health-Systems Pharmacists, Infectious Diseases Society of America, Surgical Infection Society, and Society for Healthcare Epidemiology of America (2013) recommend cefazolin as the antibiotic of choice for prophylaxis in most procedures, including colorectal procedures, where metronidazole should be added to cefazolin 1.

From the FDA Drug Label

Cefazolin for Injection, USP is indicated in the treatment of the following serious infections due to susceptible organisms: Respiratory Tract Infections: Due to S. pneumoniae, S. aureus (including beta-lactamase-producing strains) and S. pyogenes Urinary Tract Infections: Due to E. coli, P. mirabilis. Skin and Skin Structure Infections: Due to S. aureus (including beta-lactamase-producing strains), S. pyogenes, and other strains of streptococci. Biliary Tract Infections: Due to E. coli, various strains of streptococci, P. mirabilis, and S. aureus. Bone and Joint Infections: Due to S. aureus. Genital Infections: (i.e., prostatitis, epididymitis) due to E. coli, P. mirabilis. Septicemia: Due to S. pneumoniae, S. aureus (including beta-lactamase-producing strains), P. mirabilis, E. coli. Endocarditis: Due to S. aureus (including beta-lactamase-producing strains) and S. pyogenes.

The indications for Cefazolin are:

  • Respiratory Tract Infections
  • Urinary Tract Infections
  • Skin and Skin Structure Infections
  • Biliary Tract Infections
  • Bone and Joint Infections
  • Genital Infections
  • Septicemia
  • Endocarditis 2

From the Research

Cefazolin Overview

  • Cefazolin is a first-generation cephalosporin antibiotic widely used for surgical prophylaxis in various surgical disciplines 3, 4.
  • It is considered the drug of choice due to its efficacy and lower risk of allergic reactions compared to other antibiotics 3.

Efficacy in Preventing Surgical Site Infections

  • Studies have shown that cefazolin is effective in preventing surgical site infections, with a single-dose prophylaxis being sufficient in most cases 3, 5.
  • A meta-analysis of clinical trials found that cefazolin is as effective as cefuroxime, cefamandole, and ceftriaxone in preventing surgical site infections 4.

Use in Patients with Penicillin Allergies

  • Cefazolin is often underused in patients with reported penicillin allergies due to concerns about cross-reactivity 6, 7.
  • However, studies have shown that cefazolin can be safely used in patients with non-severe penicillin-class allergies, with no increased risk of severe allergic reactions 6, 7.

Administration and Dosage

  • The recommended dosage of cefazolin is typically 2g administered intravenously 30 minutes before surgery 5.
  • A single-dose prophylaxis is usually sufficient, but a second dose may be necessary if surgery is delayed or prolonged 3.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.