What is cefazolin most effective against?

Cefazolin is a first-generation cephalosporin antibiotic that is primarily effective against Gram positive bacteria. Its mechanism of action involves inhibiting bacterial cell wall synthesis, which is particularly effective against organisms that have a thick peptidoglycan layer, a characteristic feature of Gram positive bacteria.

Cefazolin is commonly used for surgical prophylaxis and the treatment of infections caused by Staphylococcus aureus, Streptococcus pneumoniae, and other Gram positive organisms. While it does have some activity against certain Gram negative bacteria, the effectiveness against these organisms is limited compared to its efficacy against Gram positives. Additionally, cefazolin is not effective against anaerobic bacteria or fungal infections, which further emphasizes its role in targeting primarily Gram positive infections.