Although some people refer to cefepime as a 4th generation cephalosporin, I prefer to think of it as an "extended-spectrum 3rd generation". Its gram-positive coverage is similar to cefotaxime and its gram-negative coverage is similar to ceftazidime. The difference is that beta-lactamases appear to have less affinity for cefepime than other 3rd generation cephalosporins and also the rate of hydrolysis of cefepime by beta-lactamases is slower. Therefore, certain strains that produce beta-lactamases that are also resistant to cefotaxime and ceftazidime, may be susceptible to cefepime. Hope this helps! Heidi Belden, Pharm.D KidsMeds, Inc.