Antifungal drugs Flashcards
Sites of action for antifungal drugs
Ergosterol synthesis inhibs
Polysaccharide synth inhibs
Inhibiting membrane- functions, Polyene macrolides
DNA/RNA synth inhibitors, antimetabolites
Mitosis inhibitors
Azoles site of action
Inhibit Ergosterol synthesis from its precursor Squalene
Ergosterol is essential for cell membrane (not cell wall)
The two classes of Azoles
Imidazoles - Ketoconazole
Triazoles - Itraconazole, Fluconazole, Voriconazole, Posaconazle
Fungal cell wall synthesis inhibitors
Echinocandins
Inhibit beta1-3 glucan synthesis which is a cell wall component.
Polyene drugs
Amphotericin B
Nystatin
Binds to ergosterol and forms membrane pores. Fungicidal.
Are technically macrolides as they are isolated from stretomyces strains of bacteria.
Heterocyclic Benzofurane
Griseofulvin
Inhibits fungal mitotic spindle formation via actions on microtubules.
Antimetabolite Antifungal
5-Flurocytosine, aka Flucytosine
for candida and cryptococcus
Inhibitors of both Ergosterol and Lanosterol
Terbinafine
Naftifine
Ciclopirox
Unclear mechanism, but used as a topical antifungal
May involve catalase and peroxidase inhibition.
Topical only azoles
Isoconazole
Clotrimazole
Tioconazole
Ecoconazole
Systemic azoles
Ketoconazole
Itraconazole
Fluconazole
Voriconazole
Generally the triazoles are given for systemic treatment
Itraconazole Voriconazole Fluconazole
Antifungal for Aspergillus
Voriconazole. Also very effective against Candida.
Spectrum of the Triazoles
Broad, for all fungi except Aspergillus
Drug of choice for Candidiasis
Fluconazole. For mucocutaneous, vaginal candidiasis
Voraconazole for Candidal esophagitis in immunocompromised.
Drug of choice for Candidiasis
Fluconazole. For mucocutaneous, vaginal candidiasis
Fluconazole or Voraconazole for Candidal esophagitis in immunocompromised, given systemically.
