Antifungals Flashcards
what are the antifungal targets?
ergosterol synthesis (membrane)
beta-glucan synthesis (cell wall)
pore formation (cell wall)
DNA synthesis
what is a yeast?
single cells, multiply by budding or fission
what is an example of a yeast?
candida, cryp
what is a mould?
multiply by spores
what is an example of a mould?
mucor, aspergillus
what are the polyenes?
nystatin, amphotericin B, natamycin
what is the polyene moa?
binds to ergosterol in cell membrane, forming a pore
polyene PKPD
poorly stable
toxic
not bioavailable
what are the triazoles?
fluconazole, itraconazole, oral miconazole
what is the triazole moa?
inhibits CYP450 in fungi that converts lanosterol to ergosterol
fluconazole
active against yeasts
high bioavailability
itraconazole
broad spectrum
bioavailability increases with acidic environment
what are the echinocandins?
caspofungin, micafungin, anidulafungin
what is the echinocandin moa?
inhibits beta glucan synthesis, increases permeability of cell wall
what is the allylamine?
terbinafine
what is the terbinafine moa?
inhibits squalene epoxidase which is involved in the ergosterol synthesis pathway
triazole pkpd
AUC:MIC 25-100
terbinafine pkpd
good bioavailability
what does terbinafine target?
moulds and dermatophytes
what is the flucytosine moa?
taken up by fungal cells then converted to 5-fu, which is incorporated into fungal RNA which blocks DNA synthesis
flucotosine pkpd
high bioavailability
pkpd T > MIC
