Anti-Fungals

Question 1

Amphotercin B

Answer 1

MAO: binds ergosterol - forms pores in membrane that allow electrolyte leakage

“tears” wholes in membrane

Systemic mycoses

Question 2

Nystatin

Answer 2

Same MAO as amphotercin but too toxic for systemic use (swish and swallow for oral Candida and topical creams)

Question 3

Flucytosine

Answer 3

MAO: inhibits DNA and RNA synthesis by conversion to 5-FU by cytosine deaminase

Use in combo w/ amphotercin in systemic (esp Crypto meningitis) - flute player in crypts

Question 4

Azoles

Answer 4

MAO: inhibit fungal ergosterol synthesis by inhibiting CYTP450 that converts lanosterol –> ergosterol

Local mycoses

Itraconazole - blasto, histo, coccidio

Voriconazole - Aspergillus and some Candida

Gynecomastia from testosterone synthesis inhibition (esp ketoconazole)

Question 5

Terbinafine

Answer 5

MAO: inhibit squalene epoxidase enzyme in fungus

For dermatophytes esp nails

Question 6

Echinocandins

Answer 6

MAO: inhibit cell wall synthesis by inhibiting synthesis of beta-glucan

caspofungin, micafungin, anidulafungin

Invasive aspergillus and Candida

Question 7

Griseofulvin

Answer 7

MAO: interferes w/ microtubule function to disrupt mitosis

Deposits in keratin-containing tissues (good for tinea)