Antibiotics Mode Of Action/resistance

Question 0

Penicillin mode of resistance

Answer 0

Beta lactamases aka penicillinase
Structural changes in PBP (MRSA)
change in porine structure (Pseudonomas)

Question 1

Penicillin mode of action

Answer 1

Binds PBP
inhibit transpeptidation
Inhibit crosslinking

Question 2

Penicillin AE

Answer 2

Hypersensitivity I-IV
(Alternatives: macrolides)
Penicillin allergy likely to be allergic to cephalosporins as well

GI distress

Question 3

Used as surgical prophylaxis___

Why?

Answer 3

Cephalosporins

Long half life

Question 4

Which generation of cephalosporins can cross BBB?

Answer 4

Second generation, specifically: cefuroxime , Ceftriaxone

Question 5

Empirical management of meningitis and sepsis

Answer 5

Third generation cephalosporins

Except Cefperazone which is lipid soluble but highly protein bound so it’s availability is low

Question 6

These bugs do not respond to 3G cephalosporins

Answer 6

LAME
listeria (effective treatment is ampicillin amoxicillin~AMOX)
Atypicals: mycoplasma,chlamydiae (use protein synthesis inhibitors)
MRSA
Enterococci (amox)

Question 7

Disulfiram like effect

Answer 7

Cefoperazone

Cefotetan

Question 8

Imipenem most be given with

Answer 8

Cilastatin
Prevents metabolism (renal dehydropeptidase inhibitor)

Question 9

Imipenem AE

Answer 9

Seizures

Question 10

Vancomycin mode of action

Answer 10

Binds to D-ala-d-ala muramyl pentapeptide to block transglycosylation (not transpeptidation) which is the process of elongation

Question 11

Erythromycin is a ______

mode of action is

Answer 11

Macrolide

Irreversibly bind 50S subunit

Question 12

Sulfonamides mode of action

Answer 12

Inhibit synthesis of Dihydrofolic Acid (essential in the synthesis of Purines, Pyrimidines, and Amino Acids)

Question 13

Polymixin MOA

effective against

Answer 13

detergent that disrupts cell membrane

topical treatment of G-, poorly absorbed

Question 14

Topical treatment of Staph Aureus

Answer 14

Mupirocin

Question 15

Metronidazole treats:

do not use with ____

Answer 15

Anaerobic infections: T. Vaginalis, C. difficile

alcohol, causes disulfiram effect

Question 16

Linezolid indicated for

Answer 16

MRSA
VRE (vancomycin resistant enterococci)
resistant Strep Pneumoniae

Question 17

Rifampin mode of action

Answer 17

Rifampin inhibits bacterial DNA-dependent RNA polymerase by binding to the b- subunit of the polymerase

Question 18

Rifampin adverse effects

Answer 18

Enhanced metabolism of other drugs such as
Anticoagulants
Contraceptives
Corticosteroids

Question 19

Quinolones MOA

Answer 19

Inhibit in
Gram+: topoisomerase IV
Gram-: topoisomerase II