Antifungals and antiparasites

Question 1

mechanism amphotericin B

Answer 1

binds ergosterol –> forms membrane pores

Question 2

clinical use amphotericin B

Answer 2

serious systemic mycoses:
  cryptococcus
  blastomyces
  coccidioides
  histoplasma
  candida
  mucor
fungal meningitis (intrathecally)

Question 3

what should you supplement when giving amphotericin B

Answer 3

K and Mg

Question 4

why do you supplement K and Mg when giving amphotericin B

Answer 4

altered renal tubule permeability

Question 5

side effects amphotericin B

Answer 5

1. fever/chills (shake and bake)
2. hypotension
   3, nephrotoxicity
3. anemia
4. IV phlebitis

Question 6

how to reduce nephrotoxicity from amphotericin B

Answer 6

hydration

Question 7

how to reduce amphotericin B toxicity

Answer 7

liposomal amphotericin B

Question 8

nystatin mechanism

Answer 8

binds ergosterol –> membrane pores (same as amphotericin B)

Question 9

how is nystatin administered?

Answer 9

topical

Question 10

clinical use nystatin

Answer 10

oral candidiasis

Question 11

treatment of typical oral candidiasis

Answer 11

nystatin

Question 12

azoles mechanism

Answer 12

inhibit fungal ergosterol synthesis by inhibiting cytochrome P-450 that converts lanosterol to ergosterol (lanosterol 14-alpha desmolase)

Question 13

clinical use fluconazole

Answer 13

cryptococcal meningitis and candidiasis in AIDS pts

Question 14

treatment of candidiasis in AIDS pts

Answer 14

fluconazole

Question 15

clinical use itraconazole

Answer 15

blastomyces
coccidioides
histoplasma

Question 16

clinical use clotrimazole and miconazole

Answer 16

topical fungal infections

Question 17

treatment of topical fungal infections (i.e. tinea circinata)

Answer 17

clotrimazole or miconazole cream

Question 18

side effects azoles (2)

Answer 18

1. testosterone synthesis inhibition (gynecomastia)

2. liver dysfunction (inhibits cytochrome P-450)

Question 19

flucytosine mechanism

Answer 19

inhibits DNA and RNA biosynthesis by conversion to 5-fluorouracil by cytosine deaminase

Question 20

clinical use flucytosine

Answer 20

systemic fungal infections (i.e. cryptococcus meningitis) in combo with amphotericin B

Question 21

side effects flucytosine

Answer 21

bone marrow suppression

Question 22

can you use flucytosine in pts with HIV?

Answer 22

NO!! (bone marrow suppression)

Question 23

what are 3 echinocandins?

Answer 23

1. caspofungin
2. micafungin
3. anidulafungin

Question 24

mechanism echinocandins

Answer 24

inhibit cell wall synthesis by inhibiting synthesis of beta-glucan

Question 25

clinical use echinocandins

Answer 25

invasive aspergillosis, candida

Question 26

side effects echinocandins

Answer 26

1. GI upset | 2. flushing (histamine release)

Question 27

terbinafine mechanism

Answer 27

inhibits squalene epoxidase

Question 28

clinical use terbinafine

Answer 28

dermatophytoses (especially onychomycosis)

Question 29

treatment of onychomycosis

Answer 29

terbinafine

Question 30

side effects terbinafine

Answer 30

1. GI upset 2. headache 3. hepatotoxicity 4. taste disturbance

Question 31

griseofulvin mechanism

Answer 31

interferes with microtubule function --> disrupts mitosis | deposits in keratin-containing tissues (i.e. nails)

Question 32

clinical use griseofulvin

Answer 32

oral tx of superficial infections | inhibits growth of dermatophytes (tinea, ringworm)

Question 33

side effects griseofulvin

Answer 33

1. teratogen 2. carcinogen 3. confusion, headaches 4. increases P-450 metabolism

Question 34

treatment for toxoplasmosis

Answer 34

pyrimethamine and sulfadiazine (same as TMP-SMX)

Question 35

what is pyrimethamine for

Answer 35

toxoplasmosis (use with sulfadiazine)

Question 36

treatment for trypanosoma brucei

Answer 36

suramin (blood) | melarsoprol (CNS)

Question 37

what is suramin for?

Answer 37

trypanosoma brucei

Question 38

what is melarsoprol for?

Answer 38

trypanosoma brucei

Question 39

treatment for trypanosoma cruzi

Answer 39

benznidazole or | nifurtimox

Question 40

what is benznidazole for?

Answer 40

T. cruzi

Question 41

what is nifurtimox for?

Answer 41

T. cruzi

Question 42

treatment for leishmaniasis

Answer 42

amphotericin B | sodium stibogluconate

Question 43

what is sodium stibogluconate for?

Answer 43

leishmaniasis

Question 44

chloroquine mechanism

Answer 44

blocks detoxification of heme into hemozoin --> heme accumulates, toxic to plasmodia

Question 45

clinical use chloroquine

Answer 45

plasmodia (other than P. falciparum --> resistant)

Question 46

mechanism of resistance to chloroquine

Answer 46

membrane pump --> decreases intracellular concentration of drug

Question 47

treatment of P. falciparum

Answer 47

artemether/lumefantrine or | atovaquone/proguanil

Question 48

life-threatening malaria treatment

Answer 48

quinidine or artesunate

Question 49

side effects chloroquine (2)

Answer 49

1. retinopathy | 2. pruritis

Question 50

what is mebendazole?

Answer 50

antihelminthic -- immobilizes

Question 51

what is pyrantel pamoate?

Answer 51

antihelminthic -- immobilizes

Question 52

what is ivermectin?

Answer 52

antihelminthic -- immobilizes

Question 53

what is diethylcarbamazine?

Answer 53

antihelminthic -- immobilizes

Question 54

what is praziquantel?

Answer 54

antihelminthic -- immobilizes

Question 55

treatment for flukes (trematodes) i.e. schistosoma

Answer 55

praziquantel