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Transcript of Ceorins

  • 1. Pharmacology of Cephalosporins: General OverviewFlavio Guzmn, M.D.

2. - lactams: cell wall inhibitors 3. -lactam ring

  • The -lactam ring is a common structure for:
    • Penicillins
    • Cephalosporins
    • Monobactams
    • Carbapenems
    • Bacteria will target this ring to gain resistance.

4. Cell wall inhibitors: important features

  • Cell wall inhibitors have bacericidal effect.
  • They act sinergistically with amynoglycosides
  • Time-dependent kinetics: the more time the drug binds the bacteria, the more effective it is.

5. Mechanism of action 1

  • Some PBP have transpeptidase activity.
  • Transpeptidase activity is essential in cell wall synthesis .
  • Beta-lactams bindPBP (Penicillin Binding Proteins).

6. Mechanism of action 2 7. Cephalosporins 8. Cephalosporins: characteristics 9. Chemical structure of cephalosporins

  • Derived from 7-aminocephalosporanic acid.
  • They suffer the attack of bacteria at their beta-lactam ring.

10. First gen. cephalosporins.: 11. 1st Generation cephalosporins: antibacterial coverage Active mainly against Gram positive cocci.Less active against Gram negative. 12. Clinical uses of first gen. cephalosporins 13. 2nd generation cephalosporins 14. 2nd generation cephalosporins. Antibiotic coverage

  • Increased coverage against Gram negatives, while keeping coverage against Gram +.

15. 3rd generation cephalosporins 16. 3rd generation cephalosporins Coverage Increased coverage against Gram negatives. Decreased coverage against Gram + 17. 3rd generation cephalosporins Clinical uses 18. Ceftriaxone and meningitis 19. 4th generation cephalosporins 20. 4th generation cephalosporins Antibacterial coverage Coverage against Gram + and Gram -,good activity against -lactamase producing bacteria. 21.