1st Gen (older) Cephalosporins

Use: Sx prophylaxis!; 

Mechanism: bactericidal; interfere with bacterial cell wall cynthesis like penecilins; 

DOC: E. coli, Klebsiella, Proteus

NOT effective against: MRSA, Lis. monocytogenes, enterococci, chlamydia, mycoplasma

Bacterial spectrum: E coli, klebsiella pneumoniae, proteus mirabilis

Rules:  

• In general, good  against Gram+ and moderate against gram-
• Most gram+ cocci (not enterococci, MRSA, Staph. epidermis) 

2nd Gen Cephalosporin; Intermediate Spectrum

Use: increased activity against gram - microorganisms, less active than 3rd gen.

DOC: Moraxella catarrhalis, E. coli, Klebsiella, Proteus

 Mechanism: bactericidal; interfere with bacterial cell wall cynthesis like penecilins; 

NOT effective against: MRSA, Lis. monocytogenes, enterococci, chlamydia, mycoplasma

Adverse effects; Pseduomembranous colitis (+diarrhea), superinfections (Candida, Staph. aureus etc.), disulfram-like reaction (EtOH combo); Dose depenent renal tubular necrosis, synergistic nephrotoxicity with aminoglycosides, candidiasis

Other Drugs: Cefaclor (Ceclor®)

Cefuroxime (Zinacef®)

Cefmetazole (Zefazone®)

Cefotetan (Cefotan®)

Cefprozil (Cefzil®)

Loracarbef (Lorabid®)

3rd Gen Cephalosporins

Mechanism: bactericidal; interfere with bacterial cell wall cynthesis like penecilins; 

DOC: Moraxella catarrhalis, Salmonella

Bacterial spectrum: Less active against gram - cocci, but MORE effectiv against Enterobacteriaceae including penicillinase producing strains; maybe pseudomonas aeruginosa

NOT effective against: MRSA, Lis. monocytogenes, enterococci, chlamydia, mycoplasma

Adverse effects; Pseduomembranous colitis (+diarrhea), superinfections (Candida, Staph. aureus etc.), disulfram-like reaction (EtOH combo); Dose depenent renal tubular necrosis, synergistic nephrotoxicity with aminoglycosides, candidiasis

Other Drugs: Ceftizoxime (Cefizox®)

Ceftazidime (Fortaz®)

Ceftriaxone (Rocephin®)- CNS penetration (meningitis), DOC N. for Gonorrhea

Cefixime (Suprax®)

4th Gen Cephalosporins

Mechanism: Comparable to 3rd gen but more resistant to B-lactamases; bactericidal; interfere with bacterial cell wall cynthesis like penecilins; increased ability to penetrate bacterial cell's outer membrane, lower rate of hydrolysis by bacterial beta-lactamases

Bacterial spectrum: Pseudomonas aeruginosa, enterobacter, enhanced stability against beta-lactamases; gram+ and gram-; Strep pneumo, Staph aureus, E. coli, klebsiella pneumoniae, proteus mirabilis, proteus vulgaris, neisseria gonorrhoeae

Less active against gram - cocci, but MORE effectiv against Enterobacteriaceae including penicillinase producing strains;

NOT effective against: MRSA, Lis. monocytogenes, enterococci, chlamydia, mycoplasma

PHK: Primarily renally excreted

Adverse effects; Pseduomembranous colitis (+diarrhea), superinfections (Candida, Staph. aureus etc.), disulfram-like reaction (EtOH combo); Dose depenent renal tubular necrosis, synergistic nephrotoxicity with aminoglycosides, candidiasis

PHK: IV

"Unnamed Generation" Cephalosporins

Use: effective against MRSA and VRSA!!!

Mechanism: Can bind to MUTATED Penicillin binding protein (not normal PBP though); inhibits transpeptidation of peptidoglycan chains

NOT effective against: MRSA, Lis. monocytogenes, enterococci, chlamydia, mycoplasma

Adverse effects; Pseduomembranous colitis (+diarrhea), superinfections (Candida, Staph. aureus etc.), disulfram-like reaction (EtOH combo); Dose depenent renal tubular necrosis, synergistic nephrotoxicity with aminoglycosides, candidiasis

PHK: IM, IV

Enterococci

Listeria monocytogenes

MRSA

Atypicals (Chlamydia, Mycoplasma)