Cell Wall Synthesis
Prevent bacterial cell wall from forming.
Beta Lactams
- Penicillins
- Cephalosporins
- Carbapenems
- Monobactams
*Vancomycin, Bacitracin
Note Regarding B-Lactams
If someone is allergic to penicillin, chances are they may also be allergic to other B-lactams.
Cell Membrane
Antibiotic breaks down cell membrane, everything leaks out, and the cell dies–Necrosis (disorderly, ugly) or Apoptosis (pretty, organized).
- Polymyxins
Folate Synthesis
Babies need folate for growth, which is also DNA synthesis.
- Sulfonamides
- Trimethoprim
Nucleic Acid Synthesis
Important for DNA. Need an antibiotic to attack a bug so it doesn’t grow.
- Quinolones
- Rifampin
Protein Synthesis
Inhibits protein synthesis–30S and 50S are ribosomes used for proteins.
- Tetracyclines
- Aminoglycosides
- Macrolides
- Streptogramins
*Clindamycin, Linezolid, Chloramphenicol
Penicillins (PCNs)
-cillin
Many may have allergies, so cross-sensitivity to cephalosporins.
MOA: Kill bacteria by disrupting cell walls, most effective on Gram + bacteria.
Antibacterial-Bactericidal
Adverse Effects: Anaphylaxis
Nursing Considerations:
- Anaphylaxis w/in minutes.
- Later hypersensitivity 5-7 days into course (can break into hives, body freaks out and sends out cytokines, the body goes into shock).
- Must monitor patient for AT LEAST 30 minutes after parenteral administration (looking for allergic reactions).
- Decreases effectiveness of oral contraceptives (OCPs), as it changes the flora in the body and penicillin will weaken the mechanism of action, and the OCP will not work anymore.
Beta-Lactamase Inhibitors
Bacteria produces enzymes capable of destroying penicillins, B-lactamase.
To prevent the med. from becoming ineffective, penicillin is used synergistically w/ another med. so it has a stronger chance of breaking down the cell wall as a B-lactam.
Clinical Uses: Treating polymicrobial (different bugs) infections.
Role: Prevent the breakdown of the B-lactam by organisms that produce the enzyme, enhancing antibacterial activity.
Ex. Tazobactam is used w/ a penicillin and must given over 4-6 hours.
B-Lactam (UNDERSTAND)
Bacteria work together to stop B-lactam ring from forming by antibiotics.
But, some bacteria become really resistat and produce enzymes to protect itself from B-lactam.
When B-lactam ring is broken, it’s more susceptible to cell wall destruction.
Penicillins
