What are the only cephalosporins that provide anaerobic coverage?

Cefoxitin and cefotetan are the only cephalosporins that provide significant anaerobic coverage, particularly against organisms such as Bacteroides fragilis. This characteristic makes them particularly useful in surgical prophylaxis for procedures where anaerobic bacteria are a concern, such as gastrointestinal surgery.

Cefoxitin is a second-generation cephalosporin with a broader spectrum of activity compared to its predecessors, particularly against anaerobic and some gram-negative organisms. Cefotetan, also a second-generation cephalosporin, has a similar profile and shares the ability to cover anaerobes. The inclusion of a beta-lactamase inhibitor in some formulations further enhances their effectiveness against resistant strains.

The other cephalosporins listed are less useful for anaerobic coverage. For instance, ceftriaxone and cefepime primarily target gram-negative organisms, while cefazolin and cephalexin are more focused on gram-positive bacteria. Similarly, cefuroxime and cefaclor do not offer the same level of anaerobic activity as cefoxitin and cefotetan. Thus, for appropriate treatment scenarios where anaerobic infection is suspected, cefoxitin and cefotetan would be the cephalosporins of choice