antifungals

Question 1

MOA of griseofulvin

Answer 1

• Interferes with Tubulin–> disrupts microtubule mitotic spindle formation, thereby causing mitotic arrest at the metaphase stage
• the musician Griz is NOT tubularrrr

Question 2

MOA of terbinafine

Answer 2

• Inhibits squalene epoxidase

- oil that wind turbine so it stops squeeling

Question 3

MOA of Azoles

Answer 3

Inhibits lanosterol 14alpha-demethylase

- azoles inhibit Alpha

Question 4

Itraconazole is metabolized in ____ via ____

Answer 4

• liver

- CYP3A4

Question 5

Azoles are metabolized in liver via CYP3A4, name 3 other medications that are metabolized via CYP3A4 and should not be given at the same time.

Answer 5

• Pimozide
• Quinidine
• cisapride

Question 6

Name two contraindications to using itraconazole (not related to other medications)

Answer 6

• Ventricular dysfunction/CHF

- Active liver disease or hx of liver toxicity with similar drug

Question 7

Which of the systemic antifungals has the greatest bioavailability?

Answer 7

• Fluconazole (>90%)

Question 8

Which systemic antifungal’s absorption is enhanced in acidic pH?

Answer 8

• Itraconazole

Question 9

Fluconazole is pregnancy category ____

Answer 9

• D

Question 10

Fluconazole is a potent inhibitor of ____. Don’t administer with _____

Answer 10

• CYP2C9

- erythromycin, astemizole (and other drugs on pg 47)

Question 11

Contraindications to using fluconazole?

Answer 11

• prolonged QT, tosades, Vtach, cardiac arrest
• if pt taking erythromycin, or astemizole
  (remember cardiac stuff for fluconazole)
• “the FLU affects the heart”

Question 12

Systemic form of Ketoconazole has a high rate of ___ and so is not used much anymore.

Answer 12

• hepatotoxicity

Question 13

DO NOT administer ketoconazole with ____, ____, or _____ as this can lead to serious CV events like prolonged QT

Answer 13

• Cisapride
• Terfenadine
• astemizole

Question 14

Voriconazole is mainly used for____

Answer 14

• serious invasive fungal infections in immunosuppressed hosts (invasive aspergillosis, candida)

Question 15

Unique AE’s of Voriconazole:

Answer 15

• severe phototoxicity (including psuedoporphyria, and xeroderma pigmentosum-like changes) and increased risk of SCC

Question 16

If pt has tinea capitis cuased by M. Canis, should you use terbinafine or griseofulvin?

Answer 16

• Griseofulvin is more effective than terbinafine for T. capitis caused by M. canis

Question 17

What are the triazoles?

Answer 17

• Itraconazole
• Voriconazole
• Fluconazole
• “with IVF you get triplets”