Beta Lactams Flashcards
0
Q
Penicillin G and Penicillin V Clinical Uses
A
- Penicillin G: IV form, acid labile
- Penicillin V: oral form, acid stable
- Bactericidal and requires actively growing organism
- Mostly gram + (S. pneumonia, S. pyogenes, Actinomyces) and syphilis.
- Bactericidal for gram + cocci, gram + rods, gram - cocci, and spirochetes
1
Q
Penicillin G and Penicillin V source and MOA
A
- Natural penicillins produced by fungus
- Beta lactam inhibits synth of crosslinks b/t disaccharide subunits of cell wall by binding transpeptidase
- Structural analogue of D-alanyl-D-alanine substrate transpeptidase
- Mechanism:
- Bind penicillin binding proteins
- Block transpeptidase cross linking of peptidoglycan
- Activate autolytic enzymes
2
Q
Penicillin G and Penicillin V Pharmacokinetics
A
- Good distribution except CNS
- Renal elimination
- Penicillin G is acid labile and only 1/3 oral dose active
3
Q
Penicillin G and Penicillin V Toxicities and Resistance
A
- Tox: hypersensitivity and hemolytic anemia
- Resistance: beta lactamase cleaves beta lactam ring
4
Q
Methacillin
A
- Penicillinase resistant penicillin
- Mechanism:
- Bind penicillin binding proteins
- Block transpeptidase cross linking of peptidoglycan
- Activate autolytic enzymes
- Clinical use: S. aureus except MRSA
- Resistant b/c altered penicillin binding protein target site
- Tox: hypersensitivity rxn, intestinal nephritis
5
Q
Nafcillin
A
- Penicillinase resistant penicillin
- Mechanism:
- Bind penicillin binding proteins
- Block transpeptidase cross linking of peptidoglycan
- Activate autolytic enzymes
- Clinical use: S. aureus except MRSA
- Resistant b/c altered penicillin binding protein target site
- Tox: hypersensitivity rxn, intestinal nephritis
6
Q
Dicloxacillin
A
- Penicillinase resistant penicillin
- Mechanism:
- Bind penicillin binding proteins
- Block transpeptidase cross linking of peptidoglycan
- Activate autolytic enzymes
- Clinical use: S. aureus except MRSA
- Resistant b/c altered penicillin binding protein target site
- Tox: hypersensitivity rxn, intestinal nephritis
7
Q
Oxacillin
A
- Penicillinase resistant penicillin
- Mechanism:
- Bind penicillin binding proteins
- Block transpeptidase cross linking of peptidoglycan
- Activate autolytic enzymes
- Clinical use: S. aureus except MRSA
- Resistant b/c altered penicillin binding protein target site
- Tox: hypersensitivity rxn, intestinal nephritis
8
Q
Ampicillin
A
- Extended range Aminopenicillins
- Mechanism:
- Bind penicillin binding proteins
- Block transpeptidase cross linking of peptidoglycan
- Activate autolytic enzymes
- Use: H. influenzae, E. Coli, Listeria monocytogenes, Proteus mirabilis, Salmonella, Shigella, enterococci. (HELPSS)
- Tox: Hypersensitivity rxn, ampicillin rash, psuedomembraneous colitis
- Resistance: betal lactamases cleave beta lactam ring
9
Q
Amoxicillin
A
- Extended range Aminopenicillins
- Mechanism:
- Bind penicillin binding proteins
- Block transpeptidase cross linking of peptidoglycan
- Activate autolytic enzymes
- Use: H. influenzae, E. Coli, Listeria monocytogenes, Proteus mirabilis, Salmonella, Shigella, enterococci. (HELPSS)
- Tox: Hypersensitivity rxn, ampicillin rash, psuedomembraneous colitis
- Resistance: betal lactamases cleave beta lactam ring
10
Q
Ticarcillin
A
- Antipseudomonals
- Mechanism:
- Bind penicillin binding proteins
- Block transpeptidase cross linking of peptidoglycan
- Activate autolytic enzymes
- Use: Pseudomonas spp and gram - rods; use with clavulanic acid
- susceptable to penicillinase
- Tox: Hypersensitivity rxn
11
Q
Carbenicillin
A
- Antipseudomonals
- Mechanism:
- Bind penicillin binding proteins
- Block transpeptidase cross linking of peptidoglycan
- Activate autolytic enzymes
- Use: Pseudomonas spp and gram - rods; use with clavulanic acid
- susceptable to penicillinase
- Tox: Hypersensitivity rxn
12
Q
Piperacillin
A
- Antipseudomonals
- Mechanism:
- Bind penicillin binding proteins
- Block transpeptidase cross linking of peptidoglycan
- Activate autolytic enzymes
- Use: Pseudomonas spp and gram - rods; use with clavulanic acid
- susceptable to penicillinase
- Tox: Hypersensitivity rxn
13
Q
Beta Lactamase Inhibitors
A
- Clavulanic acid, sulbactam, Tazobactam
- Added to penicillin antibiotics to protect antibiotic from destruction by beta lactamase
14
Q
Cefazolin
A
- 1st generation cefalosporins
- MOA: beta lactam drug that inhibits cell wall synthesis but less susceptible to beta lactamase
- Bactericidal
- Use: Gram + cocci, Proteus mirabilis, E. coli, Klebsiella pneumonia
- NOT effective against listeria, atypicals, MRSA, or enterococci
- Tox: Hypersensitivity rxn (cross hyersensitivity w/ penicillins in 5-10%)
- vit K deficiency
- Increases nephrotoxicity of aminoglycosides
- disulfram like rxn with alcohol