Anti-fungal Drugs

Question 1

Which drugs accumulate in the keratin?

Answer 1

Terbinafine (Lamisil) and griseofulvin

Question 2

Amphotericin B (Fungizone): Fungistatic or Fungicidal?

Answer 2

Fungicidal

Question 3

Amphotericin B (Fungizone) has less selective tox bc?

Answer 3

it also binds to mammalian cholesterol components

Question 3

Leukopenia, hypoglycemia, hypotension (IV use), nephrotoxicity, and hepatotoxicity are all common in _____ use.

Answer 3

Pentamidine (Pentam)

Question 4

Amphotericin B (Fungizone) administration?

Answer 4

IV or topical

Question 5

Prolonged high levels of _____ can cause bone marrow depression, abnormal liver function, and hair loss.

Answer 5

Flucytosine (Ancobon)

Question 6

____ is best absorbed with food.

Answer 6

Itraconazole (sporanox)

Question 7

Nystatin (Mycostatin) side effects?

Answer 7

mild, transient GI upset

Question 7

How do the triazoles work?

Answer 7

highly selective inhibition of fungal CYP450 (14-alpha-demethylase)- fungistatic

Question 7

How does Terbinafine (Lamisil) work?

Answer 7

Interferes with ergosterol synthesis by inhibiting squalene oxidase; toxic effects also from accumulation of squalene

Question 8

____ should not be used in pregnant or breastfeeding women.

Answer 8

Imidazoles

Question 9

Name the imidazoles.

Answer 9

1. ketoconazole (Nizoral)- systemic and topical 2. Clotrimazole (Lotramin/Mycelex)- topical only 3. Miconazole (Monistat)- topical only

Question 10

How does Pentamidine (Pentam) work?

Answer 10

it inhibits protein and nucleic acid synthesis

Question 12

What is Nystatin (Mycostatin) similar to?

Answer 12

Amphotericin B (Fungizone)

Question 13

How does Griseofulvin (Fulvicin) work?

Answer 13

it binds to microtubules, inhibiting fungal mitosis and interfering with processing of new cell wall components; fungistatic

Question 15

Nystatin (Mycostatin) use?

Answer 15

topical only; candida of skin, mucous membranes, GI tract

Question 15

______ is strong inhibitor of CYP3A4 drug metabolism leading to increased drug effect (or toxicity).

Answer 15

Ketoconazole (Nizoral)

Question 16

Amphotericin B (Fungizone) mechanism of action?

Answer 16

binds to ergosterol in fungal cell membrane, opening pores, leading to death (fungicidal)

Question 16

Name the echinocandins.

Answer 16

1. caspofungin (Cancidas)

Question 17

Name the triazoles.

Answer 17

1. fluconazole (Diflucan) 2. itraconazole (Sporanox) 3. terconazole (Terazole- topical only)

Question 19

How do the imidazoles work?

Answer 19

inhibit P450-dependent enzyme (14α-demethylase) resulting in decreased levels of ergosterol

Question 20

Amphotericin B (Fungizone) sequesters into?

Answer 20

liver, spleen, lymph nodes, lungs, and CNS

Question 21

How does Flucytosine (Ancobon) work?

Answer 21

it’s converted in fungal cell into 5-fluorouracil (via cytosine deaminase) which interferes with DNA synthesis

Question 24

____ is cleared primarily by renal excretion, requiring dosage reduction; also enters CNS.

Answer 24

Fluconazole (Diflucan)

Question 25

What is the agent of choice in treatment of P. jirovici (carinii) pneumonia in AIDS patients?

Answer 25

Pentamidine (Pentam)

Question 26

What is an important adverse affect of Terbinafine/Lamisil?

Answer 26

interference w/ CYP450 metabolism

Question 27

Amphotericin B (Fungizone) treats?

Answer 27

life threatening fungal infections: fungal meningitis, opportunists (Candida, Aspergillis), systemic infections (Histoplasma, Cryptococci, Blastomyces, Coccidioides, Murcomycosis, sporotrichosis); also for bladder irrigation

Question 28

_____ decreases effect of ketoconazole by inducing metabolism.

Answer 28

Rifampin

Question 29

Amphotericin B (Fungizone) excreted by?

Answer 29

kidney, biliary tract

Question 30

Amphotericin B (Fungizone) toxicity?

Answer 30

VERY TOXIC; nephro-, infusion related, anemia 2a to bone marrow depression