Antifungal Agents

Question 1

Name the drug:

Binds ergosterol –> forms pores –> alter membrane permeability –> Leak Na+, K+, H+ –> cell death

Answer 1

Polyene antibotics: amphotericin B, nystatin

Question 2

Name the drug:

Polymerized microtubules –>disrupt fungal mitosis

Answer 2

Griseofulvin

Question 3

Name the drug:

Pyrimidine analog –> inhibits fungal DNA and RNA synthesis

Answer 3

Antimetabolites: flucytosine

Question 4

Name the drug:
Blocks ergosterol synthesis by binding to and inhibiting fungal
cytochrome P450 enzyme lanosterol 14-alpha-demmthylase

Answer 4

Azoles: imidazoles, triazoles

Question 5

Name the drug:

Block ergosterol synthesis at a step other than inhibited by azoles

Answer 5

Allylamines: terbinafine

Question 6

Name the drug:

Inhibit synthesis of glucan

Answer 6

Caspofungin

Question 7

Drug of choice for most life threatening systemic fungal infections (Candida, Aspergillus, Cryptococcus)

Answer 7

Amphotericin B

Question 8

Amphotericin B

Fungicidal or fungistatic?

Answer 8

Fungicidal

Fungistatic depending on low pH, concentration, fungal organism

Question 9

T/F: Amphotericin B is poorly absorbed in GI tract

Answer 9

True

Oral admin only for infections within GI lumen (topical)

Question 10

Which of the follow is true about Amphotericin B?
A. It is highly soluble
B. It is excreted by the liver over a short amount of time
C. Resistance rarely develops
D. It is well absorbed from skin and mucous membranes

Answer 10

C

A. It is insoluable. Must be dissolved in bile salt detergent solution.
B. Excreted by kidney over prolonged amount of time
D. Poorly absorbed. Topical for superficial Candida infections

Question 11

Lipid formulation of Amphotericin B is used to target ___
High concentrations found in:
Low concentration found in:

Answer 11

reticuloendothelial system
High concentration in liver, spleen, lung
Low concentration in kidney

Useful for pts w/ renal dysfunction requiring long term amph B

Question 12

What adverse effect is nearly always associated w/ Amphotericin B?

Answer 12

Nephrotoxicity

Question 13

Which of the following is NOT a drug interaction of Amphotericin B?
A. Digitalis
B. Griseofulvin
C. Azoles
D. Aminoglycosides
E. Cyclosporine

Answer 13

B.

All others are drug interactions of Amphotericin B

Question 14

Which of the following is TRUE?
A. Nystatin has a wider spectrum than amph B
B. Nystatin is administered parenterally, orally and topically
C. Amphotericin B has a bitter, unpleasant taste
D. Nystatin is drug of choice for candida infection of oral cavity.
E. It is well absorbed from skin, mucous membranes and GI tract

Answer 14

D

A. Narrower
B. Orally and topically. Too TOXIC to be used parenterally
C. Nystatin has a bitter, unpleasant taste
E. It is NOT well absorbed from skin, mucous membranes and GI tract

Question 15

Griseofulvin

Fungicidal or fungistatic?

Answer 15

Fungistatic

Question 16

Griseofulvin administration

Answer 16

Oral

Question 17

Uses of Griseofulvin

Answer 17

Dermatophytosis (hair, nails, skin)

Question 18

Name the drug:

Contraindicated for men who want children

Answer 18

Griseofulvin

Question 19

Flucytosine

Fungicidal or fungistatic?

Answer 19

Fungistatic

Question 20

Flucytosine administration

Answer 20

Oral

Question 21

Flucytosine treats ___

Answer 21

systemic fungal infections, Severe Candida infections and Cryptococcus meningitis

Question 22

T/F Flucytosine rarely develops resistance.

Answer 22

False. Resistance is common

Should be used in combination w/ amph B

Question 23

Flucytosine is used in combination w/ ___

Answer 23

Amph B

Question 24

Which of the following is FALSE about Flucytosine?
A. Good oral bioavailability
B. Poor CNS penetration
C. Renal excretion
D. GI intolerance is an adverse effect

Answer 24

B. GOOD CNS penetration: meningitis

Question 25

T/F: Azoles bind to ergosterol to inhibit ergosterol synthesis.

Answer 25

False. Azoles do NOT bind to ergosterol. | It inhibits ergosterol synthesis by blocking fungal CYP enzyme activity

Question 26

T/F: Azoles have a lot of drug interactions

Answer 26

True

Question 27

Name 3 Imidazoles

Answer 27

Ketoconazole Micronazole Clotrimazole

Question 28

Which azole? | Greater propensity to inhibit mammalian CYPs

Answer 28

Ketoconazole Interfere w/ metabolism of other drugs --> enhance toxicity Limited use

Question 29

Which azole? | Effective topically against cutaneous candidiasis

Answer 29

Miconazole Uses: Jock itch, ringworm, athlete's foot, vaginal infections, oral thrush Limited use due to toxicity

Question 30

Which of the following is FALSE about Clotrimazole? A. Liver metabolized B. Highly effective alternative to fluconazole C. May cause minor GI upset D. Oral/topical administration

Answer 30

B. good alternative for nystatin

Question 31

Drug of choice for oropharyngeal candidiasis in AIDS patients

Answer 31

Clotrimazole

Question 32

``` Which of the following is NOT a triazole? A. Fluconazole B. Itraconazole C. Voriconazole D. Ketoconazole E. Efinaconazole ```

Answer 32

D. Ketoconazole is an imidazole Posaconazole is also a triazole

Question 33

Which of the follow is TRUE about Itraconazol? A. It has a narrower spectrum than fluconazole B. It has poor GI tract absorption C. Oral and topical administration D. Treatment of Aspergillus, fluconazole-resistant Candida infections

Answer 33

D A. Broader B. Good GI absorption C. Oral, IV

Question 34

Name the drug: | Better CNS penetration than other azoles

Answer 34

Fluconazole

Question 35

Fluconazole resistance in: (3)

Answer 35

C. krusei C. glabrata NOT active against molds

Question 36

Fluconazole administration

Answer 36

Oral, IV

Question 37

First line agent for invasive infections by Candida and refractory mucocutaneous candidiasis

Answer 37

Fluconazole

Question 38

Voriconazole is more potent in vitro against ___ (2)

Answer 38

Yeast | Mold

Question 39

Voriconazole administration

Answer 39

Oral, IV

Question 40

T/F: Voriconazole has low toxicity

Answer 40

True

Question 41

Only azole w/ significant activity against zygomycoses

Answer 41

Posaconazole

Question 42

T/F: Voriconazole has very little drug interactions

Answer 42

False. Inhibits CYP3A4

Question 43

First line therapy for aspergillosis

Answer 43

Voriconazole

Question 44

Name the drug: | A side effect that causes dose related, transient vision side effects

Answer 44

Voriconazole

Question 45

T/F: Posaconazole is poor oral bioavailability

Answer 45

False | Better when diet contains high fat

Question 46

Posaconazole uses

Answer 46

Prophylaxis of invasive fungal infection in BMT w/ GVHD and hematologic maligancy and prolonged neutropenia

Question 47

Topical treatment of onychomycosis

Answer 47

Efinaconazole

Question 48

Allylamines | Fungicidal or fungistatic?

Answer 48

Fungicidal

Question 49

``` Which of the following is FALSE about allylamines? A. Good GI absorption B. Metabolized by liver C. Oral, IV administration D. Limited drug interaction ```

Answer 49

C. Topical, oral D. True but co-admin w/ rifampicin and cimetidine affects clearance of terbinafine

Question 50

Caspofungin, micafungin, anidulafungin are ___

Answer 50

glucan synthesis inhibitors

Question 51

Used for invasive candidiasis resistant to other antifungals

Answer 51

Caspofungin: glucan synthesis inhibitors

Question 52

Only azole w/ significant activity against zygomycoses

Answer 52

Posaconazole

Question 53

Use for invasive aspergillosis/mold infections

Answer 53

Caspofungin: glucan synthesis inhibitors

Question 54

Azole of choice for crytococcal meningitis

Answer 54

Fluconazole

Question 55

Terbinafine is a ___

Answer 55

Allylamine

Question 56

Mechanism of action of terbinafine

Answer 56

Inhibit cell membrane synthesis