Week 3 Cell Wall Inhibitor Drugs

Question 1

Penicillin V and Penicillin G

Answer 1

V= oral G= IV form

Question 2

Probenecid

Answer 2

impairs renal secretion of weak acid, used to increase half life of penicillin

Question 3

Nafcillin

Answer 3

penicillinase-resistant penicillin

Question 4

Dicloxacillin

Answer 4

Penicillinase-resistant penicillin

Question 5

Clavulanate

Answer 5

Beta-lactamase inhibitor

Question 6

sulbactam

Answer 6

Beta-lactamase inhibitor

Question 7

tazovactam

Answer 7

Beta-lactamase inhibitor

Question 8

Ampicillin

Answer 8

Aminopenicillin

Question 9

Amoxicillin

Answer 9

Aminopenicillin

Question 10

Piperacillin

Answer 10

Antipseudomonal penicillin

Question 11

ticarcillin

Answer 11

antipseudomonal penicillin

Question 12

Cephalosporin

Answer 12

Inhibits cell wall synthesis by binding to penicillin binding protiens
less susceptible to penicillinases but can be inactivated by extended spectrum beta-lactamases

Question 13

Carbapenems

Answer 13

Imipenem/cilastatin, meropenem
contain beta-lactam ring and bind to penicillin binding proteins
broad but MRSA resistant
GI distress, cross allergic, renal dysfunciton

Question 14

Aztreonam

Answer 14

monocyclic beta lactams (use if patient is allergic to penicillin)
cell wall inhibitor and binds to polypeptide binding protein
gram neg rods

Question 15

Vancomycin

Answer 15

binds with high affinity to the D-alanyl-D-alanine terminus of the cell wall precursor unit, inhibitng release from the bactopreno carrier, thus preventing synthesis. Inhibits TRANSGLYCOSLASE reaction
gram +, especially MRSA and C.diff
empiric treament

Question 16

Bacitracin

Answer 16

prevents dephosphorylation of bactoprenol carrier needed for elongation of peptidoglycan cell wall NOT A BETA-LACTAM
topical, nephrotoxic when give IM

Question 17

Daptomycin

Answer 17

binds to cell membrane and aggregates leading to depolarization of membrane and cell death, bactericidal
Only gram +
Side effects- reversible organizing pneumonia binds pulmonary surfactant accumulating in pulmonary spaces

Question 18

Polymyxin B

Answer 18

binds phosphatidylethanolamine in the membrane creating holes, ultimately leading to release of cellular contents
Multidrug resistant gram negative bacilli, use in combo with other antibiotic to facilitate entry

Question 19

Beta-Lactam Antibiotics Mechanism of Action

Answer 19

binds to pencillin binding proteins of transpeptidase (which catalyze the terminal reaction in bacterial wall synthesis) and inhibits. Build up of cell wall precursors, which leads to activation of autolytic enzymes) Cell wall inhibitors weaken the cell wall when water enters through osmosis, cell bursts.

Question 20

Penicillinse- resistant penicillins

Answer 20

Nafcillin, Dicloxacillin

Same mechansim as penicillin but have larger R groups so resistant to penicillinases. Effective against ONLY GRAM +

Question 21

Aminopenicillins

Answer 21

Ampicillin, Amoxicillin
Expanded spectrum, GRAM POS AND GRAM NEG
More water soluble and can pass through porin channels
Same mechanism as penicillin, susceptible to beta-lactamases

Question 22

Antipseudomonal Penicillins

Answer 22

Ticarcillin, piperacillin
Widest spectrum, GRAM POS<, GRAM NEG, and PSEUDOMONAS
Same mechanism as penicillin, susceptible to beta-lactamases

Question 23

1st generation cephalosporin

Answer 23

Gram + cocci
surgical prophylaxis
Can’t cross blood brain barrier

Question 24

2nd generation cephalosporin

Answer 24

Gram Neg AND Gram Pos
use immediately prior to surgery to prevent infection
Can’t cross blood brain barrier

Question 25

3rd generation cephalosporin

Answer 25

Strep and more serious Gram NEG that are resistant to other beta-lactam CAN cross blood brain barrier

Question 26

4th generation cephalosporin

Answer 26

BROADEST spectrum | GRAM POS, GRAM NEG, and PSEUDOMONAS

Question 27

5th generation cephalosporin

Answer 27

Binds penicillin binding protein 2a in MRSA (mrsa has low affinity for other beta-lactams)

Question 28

Imipenem

Answer 28

carbapenem, beta lactam ring and binds to penicillin binding proteins, broad but MRSA is resistant. Administered with cilastatin- decrease cleavage of the beta-lactam ring by renal dehydropeptidase I and prevent formaiton of potentially toxic nephrotoxic metabolite

Question 29

Meropenem

Answer 29

Carbapenems

Question 30

Cilastatin

Answer 30

administered with Imipenem to decrease cleavage of the beta-lactam ring by renal dehyrdopeptidase I and prevent formation of potentially toxic nephrotoxin