As you move from first to third generation cephalosporins, what tends to increase?

The increase in Gram-negative coverage as you move from first to third generation cephalosporins is due to the structural modifications made to the cephalosporin molecule that enhance its ability to penetrate the outer membranes of Gram-negative bacteria. Each successive generation of cephalosporins has been designed to broaden the spectrum of activity and improve efficacy against a wider array of Gram-negative pathogens, including those that may have developed resistance to earlier cephalosporins.

For example, first-generation cephalosporins, like cephalexin, have strong activity against Gram-positive bacteria but limited Gram-negative coverage. In contrast, third-generation cephalosporins, such as ceftriaxone, possess enhanced activity against Gram-negative bacteria, including some strains of Pseudomonas and Enterobacter, while still maintaining reasonable efficacy against some Gram-positive organisms. This shift reflects the ongoing development and adaptation of these antibiotics to combat the evolving resistance patterns among various bacterial species.

The other options—improved Gram-positive coverage, fungal coverage, and viral coverage—do not show a similar trend with the progression through the generations of cephalosporins. In fact, while Gram-positive coverage may remain adequate, it does not typically increase proportionately