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
