Infection: Antifungals, mechanism of action + adverse effects Flashcards
What is the mechansim of action of the azoles?
Inhibit 14alpha-demethylase which produces ergosterol.
Side effects of azoles: p450 inhibition and liver toxicity
What are the adverse effects of the azoles?
P450 inhibition and liver toxicity
Azoles inhibit 14alpha-demethylase which is needed to produce ergosterol.
How does amphotericin B work?
Binds with ergosterol forming a transmembrane channel that leads to monovalent ion (K+, Na+, H+ and Cl-) leakage.
Side effects are nephrotoxicty, flu-like symptoms,
hypokalaemia, hypomagnaseamia
What are the side effects of Amphotericin B?
Side effects are nephrotoxicty, flu-like symptoms,
hypokalaemia, hypomagnaseamia.
Binds with ergosterol forming a transmembrane channel that leads to monovalent ion (K+, Na+, H+ and Cl-) leakage.
How does terbinafine function?
inhibits squalene epoxidase
How does griseofulvin function?
Interacts with microtubules to disrupt mitotic spindle.
Side effects: induces the p450 system, teratogenic.
What are the adverse effects of griseofulvin?
Induction of the p450 system, teratogenicity.
Works by interacting with microtubules to disrupt the mitiotic spindle.
How does flucytosine work?
Flucytosine is converted by cytosine deaminase to 5-fluorouracil, which inhibits TS and disrupts fungal protein synthesis.
Side effects: Vomiting.
What are the side effects of fluctyosine?
Vomiting.
Flucytosine is converted by cytosdine deaminase to 5-fluorouracil, which inhibits TS and thus disrupts fungal protein synthesis.
How does caspofungin function?
Inhibits the synthesis of beta-glucan, a major fungal cell wall component.
Side effect of flushing.
What are the adverse effects of caspofungin?
Flushing
How does nystatin work?
Binds with ergosterol forming a transmembrane channel that leads to monovalent ion leakage. Like amphotericin B.
What antifungals interfere with the p450 system?
Azoles = inhibit (also liver toxiciy) Griseofulvin = induces (also teratogenic)
What antifungals inhibit 14alpha-demethylase which produces ergosterol?
Azoles
What antifungal functions by inhibiting squalene epoxidase?
Terbinafine.