ANTIMICROBIALS Flashcards
(230 cards)
1
Q
The uptake of which type of antibiotics is inhibited by divalent cations?
A
Tetracyclines
1
Q
What are the AE (6) of sulfonamides?
A
Hypersensitivity, hemolysis in G6PD, nephrotoxicity (tubulointerstitial nephritis), photosensitivity, KERNICTERUS, and displace drugs from albumin such as warfarin
1
Q
This TB drug blocks the synthesis of mycolic acid
A
Isoniazid
1
Q
What drug is used to treat Giardia in A) Non pregnant and B) Pregnant
A
A) metronidazole B) Paramomycin
1
Q
What kind of drugs are nevirapine, delavirdine, and efavirenz?
A
NNRTI’s
2
Q
What are 3 beta-lactamase inhibitors?
A
Clavulanic acid, sulbactam, and tazobactam
2
Q
What are sulbactam, tazobactam, and clavulanic acid used for?
A
Beta lactamase inhibitors
2
Q
Which 3rd generation cephalosporin is used against Pseudomonas?
A
Ceftazidime
2
Q
With which drugs are aminoglycosides synergistic? What problems arise?
A
Cephalosporins potentiate them but they also increase the risk for nephrotoxicity
2
Q
Which 2 types of antibiotics cannot be taken with antacids?
A
Tetracyclines and Fluoroquinolones
2
Q
Which 2 antifungals affect cell wall synthesis?
A
Caspofungin and Anidulfungin
2
Q
In which tissue is griseofulvin most likely to deposit?
A
Keratin containing tissues
2
Q
What is praziquantel used to Tx?
A
Flukes such as Schistosoma
2
Q
MOA of zanamavir
A
neuraminidase inhibitor that decreases release of influenza A and B viral progeny
2
Q
What are the 2 neuraminidase inhibitors?
A
Zanamavir and Oseltamivir
3
Q
Which bacteria can you NOT use the penicillinase resistant penicillins on?
A
MRSA
3
Q
What is the MOA of cilastatin, always given with?
A
Inhibits renal dehydropeptidase I to prevent the breakdown of imipenem
3
Q
Why do you avoid tetracyclines in pregnancy?
A
Discolored teeth and inhibition of bone growth
3
Q
What is nifurtimox used to Tx?
A
Trypanosoma cruzi
3
Q
What drug can be used to treat HBV, HCV, and Kaposi’s?
A
IFN alpha
4
Q
What is the mechanism of resistance to the aminopenicillins?
A
Beta-lactamases (same as regular penicillins)
4
Q
Which monobactam prevents peptidoglycan crosslinking by binding to PBP3
A
Aztreonam
4
Q
What is the mechanism of resistance to aminoglycosides?
A
transferase enzymes that inactivate the drug via acetylation, adenylation, or phosphorylation
4
Q
How do you prophylax against recurrent UTI’s?
A
TMP-SMX
4
What is the antiviral that inhibits IMP dehydrogenase indicated for (2)?
This is ribavirin (Chronic Hepatitis C and RSV)
4
What CMV drug must be coadministered with probenecid?
Cidofovir due to nephrotoxicity
5
This drug inhibits renal dehydropeptidase I to prevent breakdown of imipenem
cilastatin
5
What is the AE of zidovudine?
anemia (NRTI)
7
This TB drug blocks arabinosyltransferase and decreases carbohydrate polymerization of the cell wall
Ethambutol
7
How do you prophylax against endocarditis from surgery and dental procedures?
Penicillins
8
Which antibiotic inhibits dihydrofolate reductase? Which drug also does this as an antineoplastic?
Trimethoprim; Methotrexate
9
Which generation of cephalosporins covers gram positive bacteria and Proteus, E. coli, and Klebsiella?
First Generation (PEcK)
9
What is the major AE of chloroquine?
Retinopathy
11
Which type of anemia is formed by trimethoprim? What could you give to rescue?
Megaloblastic anemia (lack of folate); rescue with folinic acid (leucovorin) same as for methotrexate
11
Which enzyme activates isoniazid to the active form?
Mycobacterial Catalase Peroxidase (KatG)
12
How do you prophylax against strep pharyngitis in a kid with Hx of rheumatic fever?
oral penicillin
13
What is the MOA of griseofulvin?
Interferes with fungal microtubules and disrupts mitosis
14
Which drugs block the conversion of lanosterol to ergosterol?
azoles
15
What are the 3 anti-staphylococcal penicillins?
Nafcillin, Oxacillin, and Dicloxacillin
16
MOA of oseltamivir
neuraminidase inhibitor that decreases release of influenza A and B viral progeny
17
What bugs are covered by second generation cephalosporins?
Gram positives, Haemophilus, Enterobacter, Neisseria, Proteus, E. coli, Klebsiella (HEN PEcK)
18
What drug inhibits HIV integrase
Raltegravir
19
What is the advantage of a cephalosporin over a penicillin regarding beta-lactamase?
Cephalosporins are overall less sensitive to beta lactamase
20
Which 2 antifungals affect membrane function?
Amphotericin B, Nystatin
22
Why are tetracyclines so effective against Chlamydia and Rickettsia?
They can accumulate intracellularly
23
In which setting would you choose aztreonam over aminoglycosides? Can you give both?
In renal failure because aminoglycosides are nephrotoxic. However, the two are synergistic so can be given together under other circumstances.
23
Describe the full MOA of acyclovir
Gets into cells and is monophosporylated by viral thymidine kinase to the active form. This then functions as a guanosine analog and causes CHAIN TERMINATION (no 3' OH)
25
What is the MOA of macrolides?
Bind to 23S rRNA at the 50S ribosome and prevent translocation
25
How do you treat tuberculous leprosy?
Dapsone and Rifampin
25
What is famciclovir used for?
VZV; this drug is related to acylclovir
27
MOA of ergosterol
Binds ergosterol to form membrane pores in fungi
28
What is the MOA of flucytosine? Used for?
blocks DNA and RNA synthesis by using cytosine deaminase to convert to 5 FU
28
What other disorders can hydroxychloroquine be used for aside from malaria?
Rheumatologic disorders
29
What highly virulent bug is covered by ceftaroline?
MRSA
30
Which beta-lactams may cause vitamin K deficiency? How would this manifest?
Cephalosporins, bleeding (loss of II, VII, IX, X, and proteins C and S)
31
2 antibiotic classes inhibiting 30 S
Aminoglycosides and tetracyclines
32
What are the 4 AE of vancomycin?
Nephrotoxicity, Ototoxicity, and Thrombophlebitis as well as Red Man Syndrome
32
This antibiotic blocks peptidyltransferase at the 50S subunit
Chloramphenicol
34
What is the mechanism of resistance to tetracyclines?
Decreased uptake by cells or increased efflux by PLASMID ENCODED GENES
35
Which antibiotics function by blocking DNA topoisomerase II and IV?
Fluoroquinolones
36
Which TB drug may cause optic neuropathy?
Ethambutol
37
AE of macrolides (5)
Motility issues, Arrhythmia (QT prolonged), Cholestatic hepatitis, Rash, eOsinophilia (MACRO)
38
What is the MOA of aminoglycosides
Bind 30 S ribosome to inhibit formation of initiation complex
38
What are the 2 most serious side effects of amphotericin
Nephrotoxicity and Arryhthmias (and the arrhythmias are ultimately due to the nephrotoxicity)
40
How do you prophylax against gonococcal and chlamydial conjunctivitis in a newborn?
Erythromycin ointment
41
What determines the half life of isoniazid?
whether the person is a fast or slow acetylator
41
How can you reverse the bone marrow suppression caused by NRTI's?
G-CSF and EPO
42
What do you use to treat onychomycosis?
Terbinafine
44
What is the DOC for Leishmaniasis?
Sodium Stibogluconate
45
How do you prophylax against meningitis?
Ciprofloxacin = adults; Rifampin = kids
46
Why do you avoid chloramphenicol in pregnancy?
Gray Baby syndrome, baby has low levels of UDP glucuronyl transferase
47
What must you co-administer with cidofovir?
It is nephrotoxic so it should be given probenicid and IV saline to decrease toxicity
48
What is the mechanism of resistance to penicillins?
Beta Lactamase
48
Which antibiotic is best for anaerobes below the diaphragm?
Metronidazole
49
Which ribosomal inhibitors can cause QT prolongation?
macrolides
49
Which antiviral inhibits IMP dehydrogenase?
Ribavirin
50
What is used to Tx flukes such as Schistosomes?
Praziquantel
51
What kind of bugs are covered by 3rd generation cephalosporins?
Serious gram negative infections
52
Why do you avoid aminoglycosides in pregnancy?
They are ototoxic
54
What is IFN B used to TX?
Multiple Sclerosis
55
What are the AE of ribavirin (2)?
Hemolytic anemia and SEVERE TERATOGEN
56
Which drugs inhibit squalene epoxidase and therefore prevent formation of lanosterol?
Terbinafine and Naftifine
57
How do you prevent red man syndrome?
Antihistamines and a slow infusion rate of vancomycin
58
Which azole is best for candidal infections of all kinds?
Fluconazole
59
Which tetracycline is best for a renally impaired patient?
Doxycycline because it is fecally excreted
61
This tetracycline is excreted fecally rather than renally
Doxycycline
62
What autoantibodies may be found in the serum of a person on isoniazid?
Antihistone; it causes a lupus like syndrome
63
What is the mechanism of resistance to macrolides
methylation of the 23S rRNA binding site
65
What is the MOA of chloroquine?
Blocks detoxification of heme to HEMOZOIN so heme accumulates and is toxic to plasmodia
66
Which antifungal drug interferes with microtubule function and may be carcinogenic?
Griseofulvin
68
Which cephalosporin covers MRSA?
Ceftaroline
69
Why do infants on chloramphenicol get "Gray baby syndrome"
They lack liver UDP-glucuronyl transferase to glucuronidate it
70
What are the main 3 AE of protease inhibitors?
Hyperglycemia, GI intolerance, and Lipodystrophy
72
Which 2 antifungals inhibit lanosterol synthesis?
Naftifine and Terbinafine
73
Ototoxicity with aminoglycosides is potentiated with __________ while nephrotoxicity is potentiated with \_\_\_\_\_\_\_\_\_\_\_\_\_\_
Loop diuretics; Cephalosporins
74
Which drugs are given as prophylaxis for A) Mycobacterium tuberculosis B) MAC and C) M. leprae?
A) Isoniazid B) Azithromycin (when CD4
76
Why is cefazolin used prior to surgery?
To prevent staphylococcal wound infections
78
What do you use to treat NADPH oxidase deficiency?
IFN gamma
79
Major AE of rifampin
orange body fluids and hepatoxicity (induce CYP450)
80
Which protease inhibitor is used to "boost" others by inhibiting cytochrome P450?
Ritonavir
81
Which antiviral should you use against HSV? VZV?
HSV = Acyclovir; VZV = Famciclovir
82
What is the AE of raltegravir?
hypercholesterolemia
83
What are suramin and melarsoprol used to treat?
Trypanosoma brucei
84
Which tetracycline is rarely used as an antibiotic but instead to act as a diuretic in SIADH?
Demeclocycline
85
Why do you avoid clarithromycin in pregnancy?
Embryotoxic
86
What is the utility of ritonavir vs. other protease inhibitors?
Ritonavir is used to boost the concentrations of others by inhibiting cytochrome P450
87
Which medication would increase the likelihood of tendon rupture in a patient taking fluoroquinolones?
Corticosteroids (prednisone)
88
What are the AE of cephalosporins?
Hypersensitivity, Vitamin K deficiency (bleeding), and increased nephrotoxicity of aminoglycosides
89
Aminoglycosides and tetracyclines both act on _____ S
30 S
91
What is valganciclovir?
Prodrug of ganciclovir with better oral bioavailability
92
What are the 4 AE of aminoglycosides?
Nephrotoxicity, Neuromuscular blockade, Ototoxicity, and Teratogenic
93
Which ribosomal inhibitors can cause cholestatic hepatitis?
Macrolides
95
Which azole is best for Blastomyces, Coccidiodes, and Histoplasma?
Itraconazle
97
Name 2 aminopenicillins
Ampicillin and Amoxicillin
98
What are 3 AE of ampicillin?
Hypersensitivity, Ampicillin rash if underlying mono, and pseudomembranous colitis
99
DOC for 1) T. brucei 2) T. cruzi
1) Suramin and Melarsoprol 2) Nifurtimox
101
How do you treat lepromatous leprosy?
Dapson, Rifampin, and Clofazimine
102
DOC for Trypanosoma brucei
Suramin and melarsoprol
104
What can be treated with IFN alpha? (3)
HBV, HCV, and Kaposi
105
What is the general rule for clindamycin and metronidazole?
Clindamycin = anaerobes above the diaphragm; Metronidazole = anaerobes below the diaphragm
106
Name 3 CMV drugs
Ganciclovir, Foscarnet, and Cidofovir
108
Which drugs potentiate the nephrotoxicity of aminoglycosides?
Cephalosporins
109
Which azole is most likely to cause gynecomastia?
Ketoconazole by inhibiting testosterone synthesis
110
MOA of trimethoprim
Inhibits dihydrofolate reductase
111
What cephalosporin is used prior to surgery to prevent S. aureus skin infections?
cefazolin
112
What is the MOA of tetracyclines?
Inhibit 30 S to prevent attachment of aminoacyl tRNA
114
What drug is often co-administered with ticarcillin and piperacillin? Why?
Clavulanic acid, inhibits beta lactamase
115
Which protease inhibitor can cause hematuria?
Indinavir
116
Which ribosomal inhibitor has a dose dependent risk of aplastic anemia?
chloramphenicol
117
Which antifungals inhibit ergosterol SYNTHESIS?
the conazoles
118
Which bacteria is penicillin most effective for?
Gram positives but also some gram negatives and spirochetes (Syphilis)
119
What is triple therapy for H pylori?
Metronidazole, Clarithromycin and PPI's
120
What is the MOA of ethambutol? AE?
Blocks arabinosyltransferase which decreases carbohydrate polymerization of the cell wall; optic neuropathy
121
What is the MOA of caspofungin and micafungin
inhibit cell wall synthesis by inhibiting synthesis of B-glucan
122
MOA of metronidazole?
disulfiram like reaction, headache, and metallic taste
124
How do you prevent postsurgical infection due to S. aureus?
Cefazolin
125
Which antifungals inhibit nucleic acid synthesis?
5-Flucytosine
127
What kind of bugs are covered by 4th generation cephalosporins?
Pseudomonas and gram positives
128
What 2 types of HSV infections can you use acyclovir for? What is the benefit of valacyclovir?
mucocutaneous (i.e. genitals and cold sores) and encephalitis; better oral bioavailability
129
Which types of bugs can carbapenems be used against?
Gram positive, Gram negative, and anaerobe = very wide spectrum but serious AE = seizures
130
Which CMV drug is a pyrophosphate analog?
Foscarnet
131
Which aminopenicillin has the greatest oral bioavailability?
amOxicillin (greater Oral) than ampicillin
132
What is the MOA of sulfa drugs?
They are PABA antimetabolites that inhibit dihydropteroate synthase
134
What 7 bugs are covered by aminopenicillins that are not by penicillins?
Haemophilus influenzae b, E. coli, Listeria, Proteus, Salmonella, Shigella, and Enterococci (HELPSS kill enterococci)
135
What is the most important AE of carbapenems?
Seizures! Use is therefore limited to serious drug rxns
137
Which type of antibiotics is aztreonam synergistic with?
aminoglycosides
138
What inhibits the uptake of tetracyclines?
Divalent cations: milk, antacids, or iron
139
What may relieve the bone marrow issues of trimethoprim?
Leucovorin = same as rescue for methotrexate (folinic acid)
140
Which type of bugs can vancomycin be used against?
GRAM POSITIVE ONLY
141
Name the 3 NNRTI's
Nevirapine, Efavirenz, and Delavirdine
143
Which drugs all end in -navir?
Protease inhibitors
144
In which generation of cephalosporins do you lose gram positive coverage?
3rd (ceftriaxone, cefotaxime, and ceftazidime)
145
Is it safe to give cephalosporins in a penicillin allergic patient?
yes there is low cross-reactivity between the two
146
What are the AE of penicillins (2)?
Hypersensitivity reactions and Hemolytic anemia
147
This TB drug has an unknown MOA but may acidify the intracellular environment by forming \_\_\_\_\_\_\_\_\_\_\_\_\_
Pyrazinamide; pyrazinoic aci
147
How do you treat life-threatening malaria?
Quinidine (quinine in places outside US)
149
What are 3 mechanisms of resistance to sulfa drugs?
Increased PABA production to outcompete, alteration of dihydropteroate synthase, or decreased uptake
150
Which drug is used to Tx the hypnozoites of Plasmodium vivax malaria?
Primaquine
151
Which antifungal binds ergosterol but is only available topically? Which is used systemically?
Nystatin; Ergosterol
152
What is the mechanism of resistance to ganciclovir?
mutated CMV DNA polymerase or viral kinase
153
Which drugs are indicated for both influenza A and B?
Neuraminidase inhibitors = oseltamavir and zanamavir
154
What bugs are covered by first generation cephalosporins?
Gram positives and Proteus, E. coli, and Klebsiella (PeCK)
156
What is Terbinafine? Terbutaline?
Terbinafine is an antifungal that inhibits squalene epoxidase and is used to Tx dermatophytes; Terbutaline is a B2 agonist used to relax the uterus
157
MOA of nystatin
Binds ergosterol to form membrane pores in fungi; unlike amphotericin B, only available topically because too toxic
158
Which generation of cephalosporins covers gram positive bacteria and Proteus, E. coli, Klebsiella, Haemophilus, Enterobacter, and Neisseria?
Second Generation (HEN PEcK)
159
MOA of foscarnet
Pyrophosphate analog that inhibits CMV viral DNA polymerase
160
Which antibiotic is best for anaerobes above the diaphragm?
Clindamycin
161
What is the mechanism of resistance to acyclovir?
mutation of viral thymidine kinase
163
Name 2 antipseudomonals
Ticarcillin and Piperacillin
163
What are the AE of ganciclovir?
BONE MARROW AND KIDNEY (renal toxicity, leuko, neutro, thrombocytopenia)
164
What 5 types of drugs block protein synthesis at the 50 S ribosomal subunit?
Chloramphenicol, Macrolides, Clindamycin, Streptogramins, and Linezolid
166
Which drug is indicated to treat Hep C and RSV?
Ribavirin
167
How are NNRTI's different from NRTI's?
They bind to reverse transcriptase at a different site than the NRTI's
168
What is the MOA of the azoles for antifungal therapy? How is it different from terbenafine?
Inhibition of the CYP450 that converts lanosterol to ergosterol; Terbenafine inhibits squalene epoxidase which converts squalene to lanosterol
170
What is the mechanism of resistance to chloramphenicol?
Plasmid-encoded acetyltransferase that inactivates it
171
Which electrolytes need to be supplemented when on amphotericin B?
K and Mg
172
Which azole is best for chronic suppression of cryptococcal meningitis?
Fluconazole
174
How can bacteria become resistant to fluoroquinolones?
mutation in DNA gyrase, plasmid mediated resistance, efflux pumps
175
This TB drug blocks DNA dependent RNA polymerase
Rifampin
176
What 2 bugs can TMP-SMX prophylax against in an AIDS patient? Azithromycin?
TMP-SMX = Pneumocystis when CD4
177
What is sodium stibogluconate used to Tx?
Leishmaniasis
178
How do you prevent neurotoxicity in a patient on isoniazid?
Pyridoxine (B6)
180
Why do you avoid ribavirin in pregnancy?
Teratogenic
181
Which aminoglycoside is commonly used for bowel surgery?
Neomycin
182
Which drugs block mRNA synthesis?
Rifampin
183
What is the difference between acyclovir and ganciclovir?
Not much really, both are guanosine analogs that are monophosphorylated by a viral kinase HOWEVER, ganciclovir is more effective against CMV and acyclovir is more effective against HSV
185
Compare the AE of penicillins to the penicillinase-resistant penicillins
Regular penicillins = hypersensitivity and hemolytic anemia whereas Penicillinase resistant ones are allergic rxns and interstitial nephritis
186
What is the AE of flucytosine?
Bone Marrow Suppression
187
Which NRTI does NOT have to be activated?
Tenofovir
189
Why do you avoid griseofulvin in pregnancy?
Teratogenic
190
The AE of which drug can be largely prevented by administration of histamines and a slow infusion rate?
Vancomycin (red man syndrome)
191
Which drug, related to ganciclovir, is a prodrug with better bioavailability?
Valganciclovir
192
Methylation of the 23S rRNA binding site confers resistance to \_\_\_\_\_\_\_\_\_\_
Macrolides but not telithromycin (a ketolide)
193
What is used to treat VRE?
Streptogramins (quinupristin and dalfopristin)
194
Which form of malaria is resistant to chloroquine?
P. falciparum--Tx with artemether/lumifantrine or atovaquone/proguanil
195
Why do you avoid fluoroquinolones in pregnancy?
Cartilage damage
196
What is pyrimethamine used to treat?
Toxoplasmosis
197
What is the MOA of aztreonam?
Monobactam that prevents peptidoglycan crosslinking by binding to PBP3
198
What are ticarcillin and piperacillin used for?
Antipseudomonal penicillins
199
Which drug is used against cryptococcus and is converted to 5-FU by cytosine deaminase?
Flucytosine
200
Which gene encodes HIV-1 protease?
pol gene
201
DOC for Trypanosoma cruzi
Nifurtimox
202
What kind of bacteria are aminoglycosides most effective against?
gram negative
203
What drug is impenem always adminstered with and why?
Cilastatin to decrease renal dehydropeptidase I? This would inactivate imipenem
204
What is special about tenofovir when compared to other NRTI's?
Does not have to be activated
205
What makes nafcillin, oxacillin, and dicloxacillin resistant to beta lactamases?
They have a bulky R group which sterically hinders them
206
Which type of beta-lactam have seizures as an AE?
Carbapenems
207
In which circumstance could you use foscarnet in a ganciclovir resistant strain of CMV?
If the resistance is from lack of viral kinase. Foscarnet does not require viral kinase, however, if the resistance is from viral DNA pol then neither will work
208
What is the AE of terbinafine? What is it used to treat?
abnormal LFTs; used to treat onychomycosis
209
Which bactericidal antibiotics inhibit formation of the initiation complex and cause misreading of mRNA?
aminoglycosides
210
How do you prophylax against syphilis?
Benzathine penicillin G
211
How can you reduce the nephrotoxicity of amphotericin B?
HYDRATE
212
How do you prophylax against gonorrhea?
Ceftriaxone
213
Which antifungal deposits in keratin-containing tissues?
Griseofulvin
214
What is the common toxicity of all CMV drugs?
Nephrotoxicity
215
Which drugs inhibit 50 S and prevent translocation?
Macrolides
216
Which bacteria are not affected by aztreonam?
Gram positive and Anaerobes (Dr. Randolf: Aztreonam is the atom bomb of gram negatives)
217
Which carbapenem does not require coadministration of cilastatin? What does this mean?
Meropenem, it is not degraded in kidneys by dehydropeptidase I
219
How do you prophylax against group B strep in a carrier pregnant female?
Ampicillin (intrapartum)
220
Which 30S inhibitors are bacteriostatic and bactericidal?
Bactericidal = aminoglycoside; Bacteriostatic = tetracyclines
221
Which drugs inhibit fungal cell wall synthesis by inhibiting B-glucan?
Caspofungin and Anidulfungin
222
What is the MOA of raltegravir?
inhibits HIV integrase
223
What is the MOA of ribavirin?
inhibits synthesis of guanine nucleotides by inhibiting IMP dehydrogenase
224
What is the DOC for toxoplasmosis? Prophylaxis in AIDS?
Pyrimethamine; TMP-SMX when CD4 less than 100
225
What are the AE of the penicillinase-resistant penicillins?
Hypersensitivity reactions and Interstitial nephritis
226
Which drug that treats anaerobes blocks peptide transfer at 50S?
clindamycin
227
What molecule is truly a "quinolone"?
nalidixic acid --all others are FLUOROquinolones
228
What are the penicillinase resistant penicillins?
Nafcillin, Oxacillin, and Dicloxacillin
229
Why do you avoid sulfonamides in pregnancy?
Potential for kernicterus
230
What kind of drugs are ampicillin and amoxicillin?
AMINOpenicillins
