EXAM #4: ANTIBIOTICS II Flashcards
Describe the composition of peptidoglycan.
Peptidoglycan is composed of repeating monomers of NAM-NAG-pentapeptide
What is NAM?
N-acetylmuramic acid
What is NAG?
N-acetylglucosamine
What is the function of the Penicillin-Binding Proteins?
Forming peptidoglycan by creating the NAM-NAG bonds
What category of antibiotics inhibit the PBPs?
Beta-Lacam antibiotics
What drugs are part of the B-Lactam family of antibiotics?
Penecillin
Cephalosporins
Monobactams
Carbapenems
Are the B-Lactams bacteriostatic or bactericidal?
Bactericidal
What enzyme can cause drug resistance in the B-Lactams?
Beta-Lactamase, which hydrolyzes the Lactam ring that is integral to this class of antibiotics
List the antibiotics that fall into the PCN family.
PCN G PCN V Amoxicillin Methicillin Nafcillin Oxacillin Ampicillin Piperacillin Ticarcillin Azlocillin
All end in “cillin”*
What are the key adverse effects seen with the PCN family of antibiotics?
Hypersensitivity
If a patient has a severe reaction to a PCN-type antibiotic, what should you be concerned about?
Hypersensitivity to ALL Beta-Lactam drugs, not JUST the PCNs
What is unique about the drug Methicillin?
This is a synthetic PCN-type drug that is RESISTANT to Beta-Lactamase
What PCN-type drugs are narrow spectrum?
PCN G PCN V Methicillin* Nafcillin* Oxacillin*
*Note that all three are “v. narrow spectrum” and are ALL resistant to Beta-Lactamase
What PCN-type drugs are broad spectrum?
Ampicillin Amoxicillin Piperacillin Ticarcillin Azlocillin
What is the utility of Beta-Lactamase inhibitors?
- Side-setting drug resistance mechansim
- These drugs can be CO-ADMINISTERED with PCN-type drugs
What is the hallmark Beta-Lactamase inhibitor?
Clavulanic acid
How is Clavulinc acid commonly administered?
Co-administration with Amoxicillin as AUGMENTIN
If a patient has a mild hypersensitivity reaction to PCN-type drugs, what family of drugs should you consider?
Cephalosporins
Generally, how do the Cephalosporins differ from the PCN-type drugs?
More resistant to Beta-Lactamase
What is the key adverse reaction to the Cephalosporins?
Hypersensitivity
What is the theme in terms of specificity/generation in the Cephalosporins?
- There are 4 generations - 1 is narrow (gram positive only)
- 4 is the broadest (gram positive and negative)
What is the theme in Cephalosporin generations and CNS penetration?
3rd and 4th generation Cephalosporins penetrate the BBB
What are the first generation Cephalosporins?
Cefazolin
What are the 2nd generations cephalosporins?
Cefotetan
Cefaclor
Cefuroxime
What are the 3rd generation Cephalosporins?
Ceftriaxone
Cefotaxime
Cefdinir
Cefixime
What is the 4th generation Cephalosporin?
Cefepime