Antifungals

Question 1

Amphotericin B

Answer 1

MOA: causes membrane permeability pores

SAE: Nephrotoxicity, fever, chills, vomiting, headache, hypotension

Notes: Polyene

Question 2

Caspofungin

Answer 2

MOA: inhibits beta-glucan synthase required for cell wall

Notes: Echinocandin. Active against yeast & aspergillus

Question 3

Fluconazole

Answer 3

MOA: Inhibits ergosterol biosynthesis (membrane sterol) by inhibiting fungal cytochrome P450 enzyme (14-alpha-demethylase)

Notes: Azole. Active against yeast, not aspergillus

Question 4

Voriconazole

Answer 4

MOA: Inhibits ergosterol biosynthesis

SAE: Transient visual disturbance

Notes: Azole. CYP inhibitor, so there are lots of drug-drug interactions. Active against yeast & aspergillus

Question 5

Flucytosine

Answer 5

MOA: Forms fluorouracil in cell and inhibits thymidylate synthetase, protein and DNA synthesis

SAE: rare bone marrow depression; alopecia

Notes: not usually used alone, due to rapid resistance. Penetrates CSF

Question 6

Terbinafine

Answer 6

MOA: inhibits squalene epoxidase, which is on the pathway to lanosterol and ergosterol

Notes: typically used for tx of nail infections, athlete’s foot