Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PDA Block 3 > Antifungals > Flashcards

Antifungals Flashcards

1
Q

Classification of mycoses: (2)

A
  1. systemic (potentially life threatening)

2. Superficial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Current effective antifungal agents target

A
  • membranes (ergosterol)
  • nucleic acids (limited)
  • cell wall (1 drug class)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Drugs used for systemic fungal infections

A
  • Amphotericin B
  • flucytosine
  • Imidazoles and bis-triazoles:
  • fluconazole
  • itraconazole
  • voriconazole
  • Caspofungin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Amphotericin B

A
  • effective (broad spectrum agent) for most serious systemic mycoses
  • especially those that are immediately threatening
  • Gold standard for anti-fungal effectiveness by which other drugs are judged
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

uses of amphotericine B

A

-due to side effects, only used for proven or highly suspected systemic infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

mechanism of action amphotericin B

A

-very lipophillic; binds ergosterol in fungal membranes producing rapid membrane instability/leakage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

explain the dosing of amphotericin B and the importance of it

A

Total cumulative dose is very important because if you go over 3-4 g of amphotericin B then you can get irreversible kidney damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

side effects for Amphotericin B

A
  • fever, nausea, vomiting, headache, chills
  • hypotension, hypokalemia, tachypnea
  • 90% will show nonpermant nephrotoxicity
  • permanent renal damage can occur (total dose)
  • reversible hypocromic, normocytic anemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Flucytosine (5-FC)

A
  • Serious infections: Candida, cryptococcus

- used in conjunction (synergistic) with amphotericin B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

MOA of Flucytosine (5-FC)

A

-fungi contain a cytosine deaminase not found in humans which converts 5-FC to 5-FU- metabolites of 5-FU then block nucleic acid synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

side effects of Flucytosine

A
  • nausea, vomiting diarrhea, enterocolitis
  • Leukopenia, thrombocytopenia
  • use extreme caution in those with renal insufficiency or bone marrow depression
  • reversible elevated hepatic enymes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Imidazole and triazole antifungals for serious fungal infections

A
  • fluconazole
  • voriconazole
  • itraconazole
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

MOA of the imidazoles and triazoles (fluconazole itraconazole and voriconazole)

A
  • inhibits 14-a-sterol demethylase, a fungal cytochrome P450 that converts lanosterol to ergosterol
  • net effect is inhibit ergosterol synthesis. Not a rapid onset of action because no effect on existing ergosterol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Clinical uses of Fluconazole

A
  • Cryptococcus
  • Candida: many sites including CNS and urinary
  • some C. albicans
  • some C glabrata
  • but NOT C krusei
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Clinical uses itraconazole

A
  • Blastomyces
  • Histoplasma
  • Candida in esophagus and oropharynx (NOT CNS and urinary)
  • more albicans and glabrata
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Clinical uses of voriconazole

A
  • Aspergillus
  • Candida (NOT urinary)
  • many species including glabrata and krusei
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

which of the -azoles (fluconazole, itraconazole, voriconazole) penetrate the CNS

A

Fluconazole is the only -azole that penetrates the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

which of the -azoles (fluconazole, itraconazole, voriconazole) is an active drg in the urine

A

Fluconazole if the only -azole that is active in the urine

19
Q

side effects common to fluconazole, itraconazole, voriconazole

A
  • nausea, vomiting, rash, diarrhea, headache
  • mild hepatotoxicity: discontinue with onset of liver dysfunction
  • inhibits metabolism of several other drugs: potent inhibitor os cytochrome P450s (CYP3A and 2C families) which metabolize about 70% of all drugs
20
Q

itraconazole contraindications

A
  • do not give itraconazole with other drugs that are metabolized with CYP3A4
  • potential for serious cardiovascular events including death when some of these drugs are given with itraconazole
21
Q

which of the -azoles (Fluconazole, itraconazole, voriconazole) has the LOWEST incidence of hepatotoxicity

A

-Fluconazole

22
Q

side effects uniqe to voriconazole

A
  • visual disturbances (30%)

- Photosensitive compoennt to rash

23
Q

antifungals that target cell wall

A

Caspofungin

24
Q

Caspofungin

A
  • treatment of invasive Aspergillus
  • Candidda, esophageal and systemic
  • broad species coverage including glabrata and krusei
25
Q

MOA Caspofungin

A
  • inhibits fungal cell wall synthesis by noncompetitively blocking synthesis of B (1,3) D glucan
  • no cross resistance with imidazoles and triazoles
26
Q

side effects of Caspofungin

A
  • fever, nausea/vomiting, flushing

- phlebitis at injection site

27
Q

Drugs for treatment of superficial mycoses

A
  • nystatin
  • Imidazoles and bis-triazoles
  • Fluconazole
  • miconazole
  • clotrimazole
  • itraconazole
  • Ophthalmic Infections
  • natamycin
28
Q

Fluconazole-superficial

A
  • mucous membrane Candida infections
  • oral dose
  • vaginal
  • urinary tract
  • oropharynx
29
Q

Miconazole-suerficial

A

-topical for vaginal Candida

30
Q

Clotrimazole-superficial

A
  • Candida
  • Topical use
  • oral troches or vaginal creams
31
Q

side effects Clotrimazole

A

abnormal liver function

32
Q

Itraconazole superficial infection

A
  • Candida
  • oropharyngeal ad esophageal
  • oral dose, not topical
33
Q

Nystatin

A
  • mechanism similar to amphotericin B
  • topical use for Candida
  • side effects: GI distress
34
Q

Amphotericine B superficial infection

A
  • topical

- cutaneous or mucosal Candida: not for dermatophytes

35
Q

Treatment of ophthalmic fungal infections

A

-natamycin

36
Q

natamycin

  • Use
  • Mechanism
  • toxicity
A
  • ophthalmic infections (topical)
  • specially useful for Fusarium, Cephalosporium
  • mechanism similar to amphotericin B
  • toxicity: conjunctival chemosis and hyperemia
37
Q

Topical Treatments for dermatophytes

A
  • miconazole, clotrimazole
  • tolnaftate
  • terbinafine
  • ciclopirox
38
Q

topical treatment for fungal nail infections

A
  • Ciclopirox

- Terbinafine

39
Q

Ciclopirox

A
  • FDA approved topical Rx for mild to moderate fungal nail infections
  • 48 weeks
40
Q

Terbinafine

A
  • 12 week therapy for nail infections

- blocks synthesis of ergosterol

41
Q

Terbinafine side effects

A

diarrhea, dyspepsia, abdominal pain

inhibits CYP2D6

42
Q

Griseofulvin

  • use
  • MOA
A
  • for recalcitrant dermatophytic infections of skin, hair, nails
  • treatment for tinea capitis

-interferes with microtubule function/mitotic spindle/mitosis

43
Q

Griseofulvin side effects

A
  • contraindicated in those with porphyria ad advanced liver disease
  • increased metabolism of several drugs
  • use with caution in those with penicillin allergies (bc produced in Penicillum mold)
44
Q

Itraconazole-dermatophyte

use and side effects

A

-oral 3 month therapy for fungal toenail infections

  • se:
  • nausea vomiting, rash diarrhea, headache, edema
  • inhibits metabolism of many drugs
  • discontinue if signs of liver dysfunction appear

PDA Block 3 (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions