Brainscape's Knowledge GenomeTM

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


See full index

Week 228 - Fungal Infections > Antifungals > Flashcards

Antifungals Flashcards

1
Q

Which groups of antifungals have an action that inhibits membrane synthesis?

A

Azoles

Echinocandins (Caspofungin)

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

Which groups of antifungals have an action that inhibits membrane function?

A

Polyenes

Allylamines

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

Which groups of antifungals have an action that inhibit nucleic acid synthesis and mitosis?

A

Others - Flucytosine, Griseofulvin

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

What is the mechianism of action of Azoles?

A

Inhibit 14-alpha-demethylase (cytochrome p-450 enzyme) which is responsible for producing ergosterol

=> ergosterol deplete => inhibit membrane formation

Th. fungi is killed by:

  • inhibition of growth (inhibition of membrane formation)
  • increased permeability of membrane
  • accumulation of toxic sterol intermediates in cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the interactions of Azoles with other drugs

A

Many drug interactions due to varying effects on human p450 enzymes

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

What are the two classes of Azoles?

A

Imidazoles

Triazoles

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

When are imidazoles used?

A

Only in topical treatment because of its toxicity

  • treatment of candida
  • treatment of tinea
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Give examples of Imidazoles

A

Ketoconazole
Miconazole
Clotrimazole (an active ingredient in Canesten)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Give examples of Triazoles

A

Fluconazole
itraconazole
Voriconazole

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

What can Fluconazole be used against?

A

Candida, Cryptococcus, Dermatophytes

- Candida krusei often resistant

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

Fluconazole can be administered in which ways?

A

Topical
Oral - well absorbed from GIT
Rarely IV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why does fluconazole give good systemic availability?

A

Penetrates CSF

Excreted unchanged by kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What can Voriconazole be used against?

A

Life-threatening Candida

Aspergillus infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Voriconazole can be administered in which ways?

A

Oral

IV - avoid in renal impairment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What can Itraconazole be used against?

A

Candida
Aspergillus
Cryptococcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Itraconazole can be administered in which ways?

A

Oral - varying availability

IV

17
Q

Name two side effects specific to Itraconazole

A

Negative ionotrope => decreased muscle contractions

Liver damage and drug interactions

18
Q

Name a side effect specific to Voriconazole

A

Visual impairment

19
Q

What is the mechanism of Echinocandins, specifically Caspofungin?

A

Glucan synthase inhibitors

Caspofungin = weakens cell wall via inhibiting beta-glucan synthase

20
Q

What can Caspofungin be used against?

A

Aspergillus

Candida

21
Q

In which ways can Caspofungin be administered?

A

IV only

  • must start with loading dose
  • caution in hepatic impairment
22
Q

What is the mode of action of Allylamines?

A

Inhibits ergosterol synthesis by inhibiting the enzyme squalene epoxidase
- Th. inhibits membrane synthesis

23
Q

Give examples of Allylamines

A

Naftifine

Terbinafine

24
Q

What is Terbinafine used for?

A

Superficial dermaphyte infections

- administerd topical or oral

25
Q

What is the mode of action of Polyenes?

A

Increase membrane permeability by binding to Ergosterol

- Th. pore foormation and leakage of cations

26
Q

Give examples of Polyenes

A

Amphotericin

Nystatin

27
Q

What is Amphotericin active against?

A

Systemic Aspergillus

Candida

Cryptococcus

28
Q

How can amphotericin be administered?

A

IV or intrathecally only

  • negligible GI absorption
  • high bound protein in blood
29
Q

Why may amphotericin cause hypokalaemia?

A

Due to renal toxicity effects

30
Q

What is nystatin used against?

A

Superficial candidiasis

  • topical only
  • nappy rash, thrush
31
Q

What is the mode of action of Flucytosine?

A

Inhibits DNA synthesis by inhibiting enzymes needed to produce thymidlyic acid (req. for DNA synthesis)

32
Q

Why must Flucytosine only be used in combination with Amphotericin?

A

Since resistance regularly occurs

33
Q

What is the mode of action of Griseofulvin?

A

Inhibits fungal mitosis

- used for dermatophyte infections

34
Q

What treatment would be used to treat vulvovaginal candidiasis?

A

Clotrimazole

alternative: Fluconazole

35
Q

What treatment would be used to treat fungal nail infection?

A

Terbinafine

36
Q

What treatment would be used to treat oral candidiasis?

A

Nystatin oral susension

Fluconazole = 2nd line

37
Q

What treatment would be used to treat tinea pedis (athletes foot)?

A

Clotrimazole 1% cream

38
Q

What treatment would be used to treat candidaemia (non-CNS)?

A

Fluconazole - oral

AmBisome = 2nd line

39
Q

What treatment would be used to treat aspergillosis (non-CNS)?

A

Voriconazole IV

AmBisome = 2nd line

Week 228 - Fungal Infections (3 decks)

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