Antibiotics I Flashcards
(117 cards)
1
Q
antibiotics are produced by _____ that kills or inhibits growth of other opportunistic microorganisms
A
microorganisms
2
Q
what is an indicator of an antibiotic drug’s selectivity?
A
therapeutic index
3
Q
pathogen specific and has a rapid response for sensitive organisms
A
narrow spectrum
4
Q
better for mixed infections, has gram + and gram - coverage, but may give up some effectiveness for gram + to gain effectiveness for gram -
A
broad spectrum
5
Q
since narrow spectrum antibiotics can target one or two bacteria, they will produce ____ _____ _____.
A
less side effects
6
Q
what are broad spectrum antibiotics good for?
A
empiric coverage
7
Q
why do broad spectrum antibiotics lead to super-infection?
A
they alter normal gut flora = allow more pathogenic organisms an opportunity to survive
8
Q
what spectrum antibiotics are preferred if bug is susceptible/sensitive?
A
narrow spectrum
9
Q
what will gram + stain look like?
A
blue
10
Q
what are 3 examples of gram + cocci?
A
staph
strep
enterococcus
11
Q
what will gram - stain look like?
A
pink
12
Q
what are 2 examples of gram - cocci?
A
neisseria
h. flu
13
Q
name the bacteria that is highly adaptive to surrounding environment
A
pseudomonas aeruginosa
14
Q
what are the bacteria-lacking cell wall called?
A
intracellular (atypical)
15
Q
4 beta lactam antibiotic classes that are cell wall inhibitors
A
Penicillins
Cephalosporins
Monobactam
Carbapenems
16
Q
3 antibiotics that are cell wall inhibitors, but not beta-lactams
A
Bacitracin
Cycloserine
Vancomycin
17
Q
medication that inhibits RNA transcription. what is it used for?
A
Rifampin
treats TB
18
Q
6 drug classes that inhibit protein (ribosome) synthesis that is necessary for bacterial growth
A
MALT-SO
Macrolides
Aminoglycosides
Lincosamides
Tetracyclines
Streptogramins
Oxazolidinones
19
Q
what kind of antibiotics penetrate the cytoplasmic membrane integrity of the bacteria?
A
peptide antibiotics
20
Q
what antibiotic medication inhibits nucleotide biosynthesis of bacteria?
A
trimethoprim-sulfamethoxazole
21
Q
what class of antibiotics inhibit topo-isomerase?
A
fluoroquinolones
22
Q
which antibiotic inhibits DNA replication of bacteria?
A
metronidazole
23
Q
when bacteria goes under a change to become resistant
A
vertical mutation/resistance
24
Q
when bacteria gets a resistant gene from an already-resistant organism
A
horizontal mutation/resistance
25
DNA and plasmids carrying the resistant gene transferred directly from resistant to susceptible bacteria. which gram bacteria use this?
conjugation
gram -
26
DNA and plasmids transferred via a bacteriophage (virus infects bacterium, replicates, and incorporates resistant gene). which gram bacteria use this?
transduction
gram +
27
DNA and plasmids acquired from environment (released by dead bacteria). which gram bacteria use this?
transformation
gram +
28
what gram bacteria is more worrisome? why?
gram -
less work is required for it to become resistant
29
drugs that act on targets that are essential for bacterial survival
bactericidal
30
what kinds of drugs are considered bactericidal? (2 MOAs and 1 drug class)
cell wall synthesis inhibitors
DNA synthesis inhibitors
aminoglycosides
31
drugs that act on targets that are necessary for bacterial growth, but not survival
bacteriostatic
32
what kinds of drugs are considered bacteriostatic? (3)
protein synthesis inhibitors
sulfonamides
trimethoprim
linezolid
33
linezolid is bacteriostatic against what? (2)
staph aureus
enterococcus
34
linezolid is bactericidal against what? why?
strep pneumo
strep is not as resistant (it's stupid)
35
between strep and staph, which is more resistant?
staph
36
smallest amount of antibiotic needed to inhibit the growth of bacteria
minimal inhibitory concentration
37
which 2 antibiotic classes are concentration-dependent killing?
aminoglycosides
fluoroquinolones
38
which 4 antibiotic classes are time-dependent killing?
"Bedtime Varies, Morning Comes"
Beta-lactams
Vancomycin
Macrolides
Clindamycin
39
how should a concentration-dependent killing antibiotic be administered?
dose once a day
40
how should a time-dependent killing antibiotic be administered?
dose more frequently so concentration is always above the MIC
41
since gram + bacteria has a huge cell wall that covers the penicillin binding protein, what kinds of antibiotics are important to use?
cell wall inhibitors
42
why don't gram - bacteria respond well to beta lactams?
because gram - bacteria contain a beta-lactamase that destroys beta lactam rings
43
which 2 drug classes bind to penicillin-binding proteins on the cell membrane to inhibit the last step of cell wall synthesis and weakens the cell wall?
penicillins
cephalosporins
44
narrow spectrum PCN used to treat staph and strep
penicillin-v
45
broad spectrum PCNs used to treat gram +, gram -, and gram - anaerobes (2)
amoxicillin
ampicillin
46
what do all bacterial cell wall inhibitors in beta lactam category contain?
beta lactam ring structure
47
what is a beta lactam ring structure essential for?
bactericidal activity
48
how does staph produce beta-lactamases (penicillinase); AKA enzymes for resistance?
via altered penicillin-binding-proteins
49
where are penicillins distributed to?
most body fluids (bile, serum, synovial fluid)
50
where do penicillins have poor penetration? (2)
bone
cerebrospinal fluid (unless inflamed meninges)
51
how are penicillins elminated?
renal elimination
52
since penicillins have a high TI, which patients can actually receive it? (2)
pregnancy
lactating
53
what are the 4 main ADR of penicillins?
Neurotoxic
Abdominal pain
Skin rash/Seizure
Throat closure
Yacking (vomitting)
Diarrhea (C. difficile)
54
what kind of penicillins cause concern for C. difficile (super-infection)?
broad spectrum penicillins
55
when does neurotoxicity occur in penicillins? (2)
high dose
intrathecal administration (CSF)
56
which penicillin has a high risk of interstitial nephritis?
methicillin
57
what should be avoided in patients with history of severe allergies to PCNs? why?
all beta-lactam antibiotics with a R-side chain
body forms IgE to penicillic acid (reactive metabolite)
58
which PCN has poor oral absorption because it is acid-labile?
PCN G
59
which PCN has good oral absorption because it is stable in gastric acid?
PCN V
60
what characteristics make PCN a broad spectrum? (2)
increased water solubility
increased membrane penetration
61
which amino-penicillin has a better bioavailability?
amoxicillin
62
what is the amoxicillin used as first line treatment for?
sub-acute bacterial endocarditis prophylaxis
63
what PCN is the only one still used for pseudomonas aeruginosa? what is the administration route?
piperacillin
IV
64
what is the main characteristic of anti-staph penicillins?
stable against beta-lactamase
65
what are the 3 PCNs that are combined with a beta-lactamase inhibitor?
amoxicillin/clavulanic acid (augmentin)
ampicillin/sulbactam (unasyn)
piperacillin/tazobactam (zosyn)
66
which PCN + beta-lactamse inhibitor combo has better bone penetration?
piperacillin/tazobactam (zosyn)
67
what is the use for PCN combined with B-lactamase inhibitor? (3)
severe intra-abdominal infections
severe soft tissue infections
anaerobes
68
what are the 1st generation Cephalosporins?
what do they treat?
cephalexin
cefazolin
MSSA (staph)
strep
69
which cephalosporin is a good alternative in questionable or mild PCN allergies (rash)?
1st gen cefazolin
70
which generation cephalosporins are used for anaerobes and gram -?
2nd generation (cefotetan + cefoxitin)
71
2nd generation Cephalosporins (cefotetan + cefoxitin) are first line prophylactic treatment for .....
intra-abdominal surgery prophylaxis
72
which is the only approved "anti-MRSA" cephalosporin in the US?
ceftaroline
73
what specific organisms is ceftaroline used for?
MRSA
PRSP (penicillin-resistant staph pneumo)
74
which cephalosporine generation/drug has good gram + and gram - coverage?
4th generation
cefepime
75
what are the 2 uses of 4th gen cephalosporin cefepime?
anti-pseudomonal
critically ill patients
76
which organism cannot be covered with any cephalosporin?
enterococcus
77
how are cephalosporins excreted?
kidney
78
what are 3 ADR of cephalosporins?
GI
hypersensitivity
super-infection
79
which cephalosporin generations have a cross-reactivity with penicillins?
1st gen
2nd gen
80
a patient taking a cephalosporin begins to experience N/V, flushing, tachycardia, headache, and sweating. what is this reaction called and what likely caused it?
disulfiram-like reaction
alcohol use
81
a patient taking a cephalosporin presents with bleeding. what caused this? what generation cephalosporin could they be taking?
inhibited vitamin K carboxylase = low clotting factors
2nd/3rd generation
82
which medication interacts with some 2nd and 3rd generation cephalosporins? what can the use of both together lead to?
warfarin
bleeding
83
a patient is taking a penicillin and presents with hypoprothrombinemia. what could they be taking?
piperacillin + CPH
84
which cell wall inhibitor is promoted as "non-nephrotoxic replacement for AMG"?
aztreonam
85
what does Aztreonam cover? (2)
gram -
pseudomonas
86
a patient presents with a severe gram - infection but is allergic to PCN, CPH, and carbapenems. what can they receive as treatment?
aztreonam (cell wall inhibitor)
87
how is aztreonam excreted?
renal tubules (kidney)
88
which class does aztreonam have cross resistance with?
especially with which drug?
3rd + 4th gen cephalosporins
ceftazidime
89
-penem
carbapenems (cell wall inhibitors)
90
how are carbapenems excreted?
kidney
91
why does imipenem need to be combined with cilastatin?
cilostatin inhibits dehydropeptidase that causes nephrotoxicity
92
what is an ADR of imipenem?
seizure
93
which medication do carbapenems decrease, specifically imipenem?
valproic acid for seizures
94
which carbapenem has the narrowest spectrum and long half life?
ertapenem
95
why are carbapenems considered the atomic bomb of antibiotics?
they have the broadest spectrum of all beta-lactams
96
how do carbapenems work against carbapenemase?
add a beta-lactamase inhibitor
97
which gram + bacteria is not covered by Carbapenems?
enterococcus
98
which beta-lactams are good for serious gram - infections and meningitis? (3)
broader spectrum PCN
3rd gen CPH
4th gen CPH
99
what do many use cefazolin for? and why?
surgical prophylaxis
least irritating for IM + good bone penetration
100
what are carbapenemas restricted for?
severe infections in hospital
101
name the 2 glycopeptides and their MOA
vancomycin
telavancin
inhibits late step of cell wall synthesis
102
what are the uses for vancomycin (glycopeptide)? (2)
gram +
c. difficile
103
how is vancomycin excreted?
kidney
104
what are 5 ADR to remember for vancomycin?
Nepthrotoxicity
Ototoxicity
Red man syndrome
Tissue necrosis if IM
corn protein allergy
105
when can vancomycin cause nephrotoxicity and ototoxicity?
when used with AMG
106
how does vancomycin cause red man syndrome?
releases histamine based on infusion rate
107
a glycopeptide that has large nephrotoxicity, interferes with coag test, not recommending in pregnancy, increased QT interval, and interacts with fluoroquinolones, macrolides, and antipsychotics
telavancin
108
polypeptides that inhibit cell wall synthesis (2)
fosfomycin
bacitracin
109
which polypeptide works for gram + and gram -, and is used for UTI?
fosfomycin
110
what is the dosing for fosfomycin? why?
once daily
high TI
111
what are the ADR of fosfomycin?
GI
headache
112
which polypeptide works for gram + only and is used for eye and skin infections via topical?
bacitracin
113
why isn't bacitracin used systemically?
causes renal necrosis
114
cell membrane destabilizer that is bactericidal and narrow for gram + only
daptomycin
115
what is the use for daptomycin?
vancomycin-resistant organisms
116
what are 3 ADR of daptomycin?
myopathy
rhabdo
eosinophilic pneumonia
117
if a patient is taking a statin, which antibiotic could cause myopathy and rhabdo?
daptomycin
