Beta Lactams II

1st Generation cephalosporins

effective against G+ bacteria

with moderate G- activity (E.coli., shigella, enterobacter, klebsiella, pasteurella, proteus & salmonella)

susceptible to cephalosporinases

for skin and soft tissue infections

2nd generation

broader in spectrum, generally active against Both G+ and some G-

ineffective against enterococci, P. aeruginosa (except cefoxitin), actinobacter spp. many obligate anaerobes (except cefoxitin)

3rd generation

more active against G- bacteria

used for more severe infections, including respiratory and systemic conditions

4th generation

has the broadest spectrum

cefquinome and cefepime have been utilized in animals but are subject to restrictions and regulation

cefquinome

most recently developed cephalosporin for veterinary purposes

broad spectrum

licensed for use in cattle

MOA of cephalosporins

bind to PBPs and disrupt the cell wall

with bactericidal effect

weak acids

Adverse side effects

possible of allergic reactions in small animals

cross sensitivity with PCNs

GIT disturbances

may lead to superinfection

Reptiles

Slow excretion in this species which requires long dosing interval

birds

rapid elimination and poor GIT absorption in this species which requires high dose & frequent administration