What is the only fourth-generation cephalosporin?

What is the only fourth-generation cephalosporin?

• A. Cefuroxime
• B. Cefixime
• C. Cefepime
• D. Cefotetan

Answer: (C)

The concept tested is how cephalosporins are categorized by generation, which tracks changes in antimicrobial spectrum and beta-lactamase stability. Fourth-generation cephalosporins expand activity notably against Gram-negative pathogens, including Pseudomonas, while maintaining good Gram-positive activity and improved stability to beta-lactamases. Cefepime is the only fourth-generation agent here, giving it broad Gram-negative coverage that includes Pseudomonas and solid activity against many Enterobacterales, with good stability to beta-lactamases. The other drugs represent earlier generations: cefuroxime is second-generation with enhanced activity against HNPEK and some Gram-positives; cefixime is third-generation (oral) with strong Gram-negative activity but less Pseudomonas coverage; cefotetan is a second-generation cephalosporin with anaerobic activity and a side chain that can cause disulfiram-like reactions and affect vitamin K. Therefore, cefepime is the best answer.

The concept tested is how cephalosporins are categorized by generation, which tracks changes in antimicrobial spectrum and beta-lactamase stability. Fourth-generation cephalosporins expand activity notably against Gram-negative pathogens, including Pseudomonas, while maintaining good Gram-positive activity and improved stability to beta-lactamases.

Cefepime is the only fourth-generation agent here, giving it broad Gram-negative coverage that includes Pseudomonas and solid activity against many Enterobacterales, with good stability to beta-lactamases. The other drugs represent earlier generations: cefuroxime is second-generation with enhanced activity against HNPEK and some Gram-positives; cefixime is third-generation (oral) with strong Gram-negative activity but less Pseudomonas coverage; cefotetan is a second-generation cephalosporin with anaerobic activity and a side chain that can cause disulfiram-like reactions and affect vitamin K. Therefore, cefepime is the best answer.