Antifungals

Question 1

Polyenes. Naturally occurring or synthetic?

name two

Answer 1

Naturally occurring

amphotericin B
nystatin

Question 2

Azoles. Naturally occurring or synthetic?

name one

Answer 2

Synthetic

Ketoconazole

Question 3

Amphotericin B

Superficial or systemic:
Mechanism:
Route:
Adverse effects:

Answer 3

Superficial or systemic: Systemic

Mechanism: Bind to sterols in cell membrane lining. Makes holes in fungi cell membranes

Route: SLOW IV injection

Adverse effects: Higher concentrations bind to cholesterol - toxicity. Renal toxicity, K+ loss (need supplements). Liver toxicity, Impairs hepatic functions (assess for liver functions by measuring hepatocyte enzyme levels prior to administration)

To reduce the severity, pretreat with:
antipyretic (acetaminophen)
antihistamines (diphenhydramine)
anti-emetics

Question 4

Ketoconazole

Superficial or systemic:
Mechanism:
Route:

Answer 4

Superficial or systemic: Systemic

Mechanism: Inhibit sterol-altering enzyme Cyp P450 enzymes. Less ergosterol is made, Leads to altered cell membrane

Route: Multiple administration routes.

Question 5

Nystatin

Superficial or systemic:
Mechanism:
Route:

Answer 5

Superficial or systemic: Superficial

Mechanism: Bind to sterols in cell membrane lining. Makes holes in fungi cell membranes

Route: Oral infections - swished in mouth. Placed in vagina for infections?

Note Higher concentrations bind to cholesterol - toxicity

Question 6

Agent of choice for the treatment of severe systemic mycoses?

Answer 6

Amphotericin B