Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Pharm Exam 4 > 48/49: Antibiotics II > Flashcards

48/49: Antibiotics II Flashcards

1
Q

peptidoglycan is composed of…

A

chains of repeating monomers of the disacchride subunits: NAM-NAG-pentapeptide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

enzymes join monomers together to form NAM-NAG chains

A

transglycosylase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

enzymes bind the NAM-NAG chains into a rigid structure by adding pentaglycine crosslinks between pentapeptide residues on adjacent chains

A

transpeptidase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are peniclinin-binding proteins?

A

peptidoglycan is maintained by the enzymes that create the bonds between NAM-NAG peptidoglycan monomers and between NAM-NAG chains in the layer

selective b-lactam antibiotics bind selectively to different PBPs and this contributes to the sensitivity of bacterial strains to individual penicillins and cephalosporin antibacterial agents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

b-lactam compounds include (4)

A

penicillins
cephalosporins
monobactams
carbapenems

these agents are bactericidial

susceptible to b-lactamase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

MOA penicillins

A

bind to and inhibit PBP enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

key adverse effects of penicillins

A

hypersensitivity 5-7%

rash, hives, itching, respiration difficulty, anaphylaxis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q 
ampicillin
amoxicillin
piperacillin
ticarillin
azlocillin
A

all “broader” penicillins

penicillin G and V
methicillin
nafcillin
oxacillin 
= narrower spectrum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

which penicillins are b-lactamase resistant?

A

the group of vey narrow spectrum

methicillin
nafcillin
oxacillin

all the rest are sensitive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

______ used in combination with penicillins to increase effectiveness

A

clavulanic acid (b-lactamase inhibitor)

amoxicillin & clavulanic acid = augmentin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

advantages of cephalosporins over penicillins

A
  • more resistant to b-lactamase
  • less % adverse effects

generally used if penicillins are not well tolerate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

MOA cephalosporins

A

bind to and inhibit the PBPs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

key adverse effect cephalosporins

A

hypersensitivity 2%

rash, hives, itching, respiration difficulty, anapylaxis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

4th generation cephalosporins have a more _____ spectrum than 1st gen

A

broad

broader spectrum with increasing generation

1st g: +
2nd g: + and some -
3rd g: + and -
4th g: + and -

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

which cephalosporins can enter the CNS?

A

3rd and 4th gen

cefdinir
cfixime
ceftriaxone

cefepime

and 2g: cefuroxime

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

which cephalosporin gen is b-lactamase resistant?

A

4th gen

cefepime

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

only mono bactam agent

A

aztreonam

only gram -
penetrates CSF
b-lactamase resistant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

MOA aztreonam

A

bind to and inhibit PBPs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

key adverse reaction monobactams

A

hypersensitivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

are carbapenems resistant to b-lactamase?

A

yes but susceptible to similar enzyme carbamenemase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

______ inactivated in kidney so it is administered with cilastatin to prevent this inactivation

A

imipenem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

MOA carbapenems

A

bind to and inhibit the PBPs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

key adverse effects carbapenems

A

GI

nausea, vomiting, & diarrhea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

MOA vancomycin

A

prevents elongation of the peptidoglycan cell wall structure by binding to pentapeptide and acting as steric inhibitor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
key adverse effect vancomycin
flushing "red neck" or "red man syndrome" also ototoxicity
26
MOA bacitracin
blocks incorporation of aa and nucleic acids into cell wall
27
common use fosfomycin
uncomplicated UTI
28
MOA fosfomycin
blocks an early step in cell wall synthesis by preventing syntheiss of UDP-N-acetylmuramic acid
29
prtn synthesis inhibitors include...
aminoglycoside, macrolides, tetracycline and a few other specific compounds
30
what are the steps of prtn synthesis which can be targeted by antibiotics?
step1: charged tRNA binds to A site step2: peptidyl tRNA, peptide bond formation between grwoing aa chain and new aa in A site step3: the newly uncharged tRNA exits step4: the now-longer aa chain translocates to P site
31
why target the 50S and 30S subunits?
unique to prokaryotes
32
what ___mycins are not aminoglycosides?
azithromycin clarithromycin and eryhtromycin are macrolides fosfomycin is a phosphoenolpyruvate daptomycin is a lipopetide clindamycin is other
33
name the aminoglycosides
``` amikacin gentamicin kanamycin neomycin streptomycin tobramycin ```
34
MOA aminoglycosides
bind to 30S and block formation of initiation complex (step 1)
35
key adverse effects aminoglycosides
nephrotocicity (6-7% renal tubular necrosis) ototoxicity (2%) dizziness, ringing, fullness
36
MOA macrolides
binds to 50S and impairs the translocation to the P site (step 4)
37
name the macrolides
azithromycin clarithromycin erythromycin
38
key adverse effect macrolides
GI stomach cramps, nausea, vomiting, diarrhea (b/c motilin receptor agonist)
39
MOA tetracyclines
binds to 30S subunit of ribosome and prevents binding of new tRNA to A site (step 1)
40
key adverse effect of tetracyclines
nutrient interactions : binds calcium which results in growth of calcified tissue disrupts normal flora photosensitivity
41
MOA clindamycin
bind to 50S subunit of the ribosome and prevents the formation of initial complexes (step 1) and translocation to P site similar to macrolides
42
key adverse effects clindamycin
GI: nausea, vomiting, diarrhea | **c. diff infection
43
MOA chloarmphenicol
binds to 50S subunit of the ribosome and prevents transpeptidation or peptidyl bond formation (step 2)
44
key adveres effects chloramphenicol
gray baby syndrome: infants lack glucuronic acid conjugation (gray color, scock, comiting, cascualr collapse) blood: suppression of red cell production
45
MOA linezolid
inhibits prtn synthesis by binding to the P site of the 50S ribosome and inhibiting the formation of the ribosomal-mettRNAcomplex (very first step 1)
46
key adverse effect linezolid
blood myelosuppression
47
MOA sulfonamides
compete with PABA for the enzyme diydropteroate synthase and block dihydrofolic acid synthesis and thus DNA synthesis
48
key adverse effects sulfonamides
skin: hypersensitivity, photosensitivity, steven-johnson
49
common use trimethoprims
UTIs
50
MOA trimethoprims
inhibitor of bacterial dihydrofolate reductase resulting in impaired DNA synthesis
51
key adverse effect trimethoprims
blood: bone marrow suppresion, megaloblastic anemia, leukopenia, granulocytopenia
52
TMP-SMX =
trimethoprim and sulfamethoxazole synergistic effects commonly used to treat UTI and prostatitis
53
what drug discussed is effective against anthraz?
fluoroquinolones
54
MOA fluoroquinolones
disrupt the winding of DNA and the separation of DNA strands during transcription and replication. These agents specifically inhibit the enzymes topoII and topoIV
55
key adverse effects fluoroquinolone
GI Drug-nutrient: binds divalent cations and prevents absorption cardio - QT prolongation
56
group 1 --> 3 of fluoroquinolones
1 least active 2 both neg and pos, mostly neg 3 best against pos
57
what organisms can metronidazole target?
anaerobic bacteria and protozoa
58
MOA metronidazole
prodrug | undergoes chemical rxn in organsims and disrupts DNA
59
key adverse effects metronidazole
- GI | - metabolism - no alcohol!
60
MOA daptomycin
binds to membrane and causes depolarization of membrane - bactericidial calcium dependent insertion in membrane
61
key adverse effects daptomycin
musculoskeletal - myopathy, rhabdomyolysis
62
MOA polymyxinB
bind to phospholipids in cell membrane and disrupt structure "punchholes" in gram neg only
63
Mechanisms of resistance for penicillins and cephalosporins
1. expresion of b-lactamase 2. alteration in PBP binding to drug 3. alteration in porin function
64
mechanisms of resistance for aminoglycosides
1. expression of enzymes that alter chemical structure of drug
65
mechanisms of resistance for macrolides
1. transport of drug out of cell (drug efflux) | 2. alterations of drug binding to 50S ribosomal subunit
66
mechanisms of resistance for tetracyclines
1. transport of drug out of cell (drug efflux)
67
mechanisms of resistance for sulfonamides
1. less sensitive drug target 2. increased synthesis of PABA 3. scavenge or use other sources of folic acid
68
mechanisms of resistance for fluoroquinolones
1. less sensitive drug target | 2. drug efflux
69
mechanisms of resistance for chloramphenicol
1. expression of inactivating enzymes

Pharm Exam 4 (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions