Anti fungal

Question 1

Drugs binding to fungal cell membrane ergosterol and increase membrane permeability

Answer 1

Amphoterecin
Nystatin

Question 2

Drugs that inhibit ergosterol synthesis

Answer 2

AZOLE group
Fluconazole
Itraconazole
Voriconazole

Question 3

Drugs that inhibit nucleic acid synthesis

Answer 3

5-flucytocine.

Question 4

Drugs that inhibit ergosterol + lanosterol synthesis

Answer 4

Terbinafine

Question 5

Amphoterecin B

Answer 5

Toxic but still used
Mechanism:
- binds to ergosterol
- alters permeability by forming pores
- K+, Na+, Mg, H+ leak out causing cell death
Application:
- topical, vaginal, cutaneous
Adverse effects:
-Nephrotoxicity
-fever
-Hypotension
-Hypokalemia

Question 6

Azoles - synthetic and broad spectrum fungicidal properties.

Answer 6

mechanism:
inhibits 14 alpha demethylase
leads to cascade of membrane abnormalities.
Invasive aspergillosis:
Itraconazole and Voriconazole used most
Adverse effect:
well tolerated
vomit
abdominal pain
rash

Question 7

Flucytosine - Narrow spectrum

Answer 7

Analogue of cytosine.
Mechanism:
inhibit fungal DNA synthesis
Uses:
candidiasis and cryptococcal meningitis - combo therapy
Adverse:
bone marrow depression
GI disturbance
Liver dysfunction
Thrombocytopenia

Question 8

Terbinafine

Answer 8

Mechanism:
inhibits enzyme squalene oxidase that converts squalene into lanosterol
Uses:
orally given
topically given for candida/ dermatophytes
Adverse:
well tolerated, headache, gastric upset, liver enzymes elevations.