Second-Generation Cephalosporins

General Characteristics:
- No member is active against enterococci or P. aeruginosa.
- Can be used to effectively treat respiratory tract infections, showcasing their versatility.
- Extended spectrum includes G(-) bacteria, making these antibiotics particularly useful in a clinical setting.
Microbial Activity:
- Active against specific organisms classified under the acronym HENMPEcK:
  - Haemophilus influenzae
  - Enterobacter
  - Neisseria
  - Moraxella catarrhalis
  - Proteus mirabilis
  - E. coli
  - Klebsiella pneumoniae
- These medications are commonly utilized for treatment purposes, particularly for sinusitis, otitis media, and lower respiratory tract infections.
Pregnancy Category:
- All second-generation cephalosporins are categorized as pregnancy category B, suggesting they are generally considered safe to use during pregnancy when necessary.
Notable Antibiotics:
- Cefuroxime (PO and IV):
  - Available in both oral and intravenous formulations.
  - Involves axetil for its oral formulation, enhancing bioavailability.
  - Demonstrates improved activity against Pneumococcus and Haemophilus influenzae, making it a preferred choice sometimes for community-acquired pneumonia treatment.
  - Commonly prescribed at a dosage of 250-500 mg PO administered twice daily.
- Cefaclor:
  - Efficiently active against H. influenzae but lacks effectiveness against Serratia or Bacteroides fragilis.
- Cefotetan and Cefoxitin (IV):
  - Both have activity against Bacteroides fragilis and certain Serratia strains, allowing their use in treating abdominal and pelvic infections such as peritonitis, diverticulitis, and pelvic inflammatory disease.
  - Cefoxitin is particularly noted for its improved stability against extended-spectrum beta-lactamases produced by E. coli and Klebsiella species, enhancing its efficacy in resistant infections.