IDIOT

Cephalosporin , any of a group of more than 20 antibiotics derived from species of fungi of the genus Cephalosporium and closely related chemically to penicillin. It act against both gram-positive and gram-negative by inhibiting bacterial cell wall synthesis and it is also a bactericidal.

First-generation cephalosporins are predominantly active against gram-positive bacteria.

Second-generation cephalosporins have a greater Gram-negative spectrum while retaining some activity against gram-positive cocci.

Third-generation cephalosporins have a broad spectrum of activity and further increased activity against Gram-negative organisms. Some members of this group have decreased activity against Gram-positive organisms.

Fourth-generation cephalosporins are extended-spectrum agents with similar activity against Gram-positive organisms as first-generation cephalosporins. They also have a greater resistance to beta-lactamases than the third-generation cephalosporins. Many can cross blood brain barrier and are effective in meningitis. They are also used against Pseudomonas aeruginosa.