Pharmacology - Antimicrobial Therapy I - Jeffrey Steele Flashcards
Class: Penicillins
Beta-lactam
Class: Cephalosporins
Beta-lactam
Class: Aztreonam
Monobactam
Class: Vancomycin
Glycopeptides
Class: Telavancin
Dalbavancin
Oritavancin
Lipoglycopeptides
Beta lactams, Monobactams, Glycopeptides and Lipoglycopeptides all act:
on the cell wall of bacteria
MOA: Beta-lactams
Bind to (acylation of) PBPs (penicillin binding proteins)
- -PBPs polymeriza the glycan strand (transglycosylation)
- -PBPs cross-link between glycan chains (transpeptidation)
What are mechanisms of resistance against beta lactams?
Enzymatic Destruction - by gram negative bacteria;
Reduced permeability;
Target site alteration
Beta-lactams do not work on:
Mycoplasma pneumoniae;
Chlamydophilia pneumoniae
–these bugs lack cell walls
Legionella MRSA (except for ceteroline = 5th gen cephalosporin)
Side effects: Beta lactams
Drug fever Acute interstitial nephritis Seizures at high doses Diarrhea Delayed hypersensitivity reaction - rash
What are the natural penicillins?
Penicillin G
Penicillin V
Class: Oxacillin
Nafcillin
Dicloxacillin
Penicillinase-resistant penicillins aka antistaphylococcal penicillins
Penicillins - Beta-lactams
Class: Ampicillin
Amoxicillin
Aminopenicillins
Amino group increases hydrophilicity - improved penetration into gram negative cell membrane
Class: Ticarcillin
Piperacillin
Anti-pseudomonal penicillins
Use: Penicillin G, G procaine, G benzthine, V
Streps;
Mostly gram pos aerobic organisms;
Spirochetes - Treponema palladium;
Some enterobacteriaciae
Addition of what to Penicillin is recommended for use against odontogenic infections?
Metronidazole
recommended for b-lactamase producing aerobes
Use: Anti-staph penicillins ie oxacillin
MSSA - skin and soft tissue infections, joint infection, bacteremia, endocarditis;
(Strep)
T/F: Anti-staph penicillins are superior to vancomycin for MSSA infections.
True
Oxacillin
Nafcillin
Dicloxacillin
Adverse events: Oxacillin
Hepatotoxicity, neutropenia (delayed)
Adverse events: Nafcillin
Hepatotoxicity, neutropenia (delayed) and thrombophlebitis
What anti-staph penicillins require frequent dosing due to their short half life?
Oxacillin, Nafcillin
What is the drug of choice for enterococci?
Ampicillin (Aminopenicillin class)
–also for Listeria
Use: Amoxicillin
Otitis media; Upper and lower RTI; Lyme disease; Streps ie S. Pneumo **also covers haemophilus which causes upper ear/RTI stuff (for the unvaccinated child)
Use: IV Ampicillin
Listeria - meningitis;
Enterococcal infections
Used with gentamycin for endocarditis
Which aminopenicillin has better bioavailability?
Amoxicillin > Ampicillin
The antipseudomonal penicillins, piperacillin and ticarcillin, are always used in conjunction with:
B-lactamase inhibitors to expand spectrum to include beta-lactamase-producing organisms