antifungal Flashcards
what is the moa of echinocandins
they noncompeteively inhibit 1,3 B-D glucan synthase
an enzyme that forms glucan polymers in the fungal cell wall
this component is only found in cell wall of fungi NOT IN BACTERIA NOR ANIMAL CELLS
Where do candins come from
they are semisynthetic
derived from the fungus Glarea Lozoyensis
explain candins structure
ampophilic cyclic hexapeptide with an N-acyl side chain
who are penicillins of anti fungal
echinocandins
spectrum of candins
narrow spectrum that is limited to candida species and to a lower extent = Aspergillus niger
precursor of ergosterol?
Lanosterol
main side effects of candins
nausea
vomiting
diarrhea
heptene polyene
amophcetrin B
7 trans or E conjugated double bonds
polyenes activity due to
Trans or E configuration
therefore must be protected from light (UV or heat) in amber colored containers or else isomerization will occur and will yield inactive reduced activity Cis or Z
which polyene can be given IV and why
Amph B
because its the least toxic and most potent
whats the main toxicity from polyenes
nephrotoxicy after IV
therefore must be given at recommended doses
moa of azoles
they inhibit synthesis of ergosterol by inhibiting the enzyme CYP51 aka 14 a demethylase this enzyme is CYP3A-dependent
it works to convert lanosterol to ergosterol but azoles inhibit that leading to accumulation of the precursor and depletion of the ergosterol thus cell death etc
moa of azoles
they inhibit synthesis of ergosterol by inhibiting the enzyme CYP51 aka 14 a demethylase this enzyme is CYP3A-dependent
it works to convert lanosterol to ergosterol but azoles inhibit that leading to accumulation of the precursor and depletion of the ergosterol thus cell death etc
AE of ketoconazole
adrenal insufficiency
anorexia
V/N
Hepatic dysfunction
AE of itraconazole
hepatoxicty
what is itraconazole extensively used in treatment of what
dermatophytoses, especially onychomycosis
brand name of fluconazole
Diflucan
azole of choice for treatment and secondary prophylaxis cryptococcal meningitis
Fluconazole
fluconazole used for
- systemic candidiasis
-treatment and secondary prophylaxis for cryptococcal meningitis
most widely used antifungal drug
fluconazole
fluconazole resistance
enzyme mutation and efflux - resistance develops easily
which antifungal drug absorption is not dependent on gastric pH
fluconazole (diflucan
voriconazole is used for
treatment of choice for invasive aspergillosis
voriconazole is infective against
mucormycosis
broadest spectrum of the azole family
posaconazole - candida , aspergillosis,
zygomycosis , mucormycosis (only one thats active against them)
Which antifungal has oral delayed release and suspension
posaconazole
Brandname for terbinafine
Lamisil !!!!!!
terbinafine is never given for
primary nor severe infections
antifungal drug thats kertaophylic
terbinafine
which antifungal have good CSF penetration
Fluconazole (IV)
Voriconazole
Posaconazole (but low blood levels)
AMB ( ONLY WHEN GIVEN INTRATHECALLY)
Which combo must be avoided when given eichoncandins and what happen
capsofungin with cyclosporin leads to elevated liver enzymes
what would you treat neutropenic fever with
eichocandins
bistrizole
found in fluconazole we have two imidazole rings in total
who is structurally related to fluconazole
voriconazole with a fluoridated pyramidine
what is a nonnegotiable for polyenes
THEY ARE NEVER ORALLY
WE ONLY GIBE AMB AS IV