SECOND-GENERATION CEPHALOSPORIN - Second-generation cephalosporins have enhanced activity against Escherichia coli, Klebsiella species, and Proteus mirabilis; in addition, they have greater activity in vitro against a larger number of gram-negative bacteria, including Haemophilus influenzae, indole-positive Proteus, Neisseria meningitidis, N. gonorrhoeae, and some strains of Serratia and Enterobacter species. Second-generation cephalosporins include cefaclor, cefamandole, cefmetazole, cefonicid, cefotetan, cefoxitin, cefprozil, and cefuroxime.