Pharm - Antifungals Part 2 Flashcards
name 3 echinocandins
caspofungin
micafungin
anidulafungin
general structure of echinocandins
large, cyclic peptides with long fatty acid chains
MOA echinocandins
NONCOMPETITIVE inhibitor of B 1,3-glucan synthase
thus inhibits production of B 1,3 glucan polysaccharide, important component of fungal membrane
true or false
echinocandins are competitive inhibitors of B 1,3-glucan synthase
FALSE
noncompetitive
route administration echinocandins
IV
resistance mechanism to echinocandins
mutation in B 1,3-glucan synthase
AE echinocandins
generally well tolerated
can cause GI issues and flushing
can echinocandins be used in pregnancy
NO - contraindicated
caspfungin ____ the levels of tacrolimus
increases
cyclosporine ____ the levels of caspofungin
increases
what will rifampin do to caspofungin levels
DECREASE
rifampin is a strong CYP INDUCER
2 ORAL drugs for mucocutaneous fungal infections
griseofulvin
terbinafine
MOA of griseofulvin
inhibits fungal mitosis (division) by inhibiting spindle formation
does this by binding to tubulin - disrupts mitotic spindle and inhibits fungal mitosis
true or false
griseofulvin is fungicidal
FALSE
fungistatic
griseofulvin absorption increases with…
fatty foods
griseofulvin is used for the systemic treatment of what 2 things
dermatophytosis (ringowrm - skin , hair, nails)
onychomycosis (nails)
how does griseofulvin have a stronger affinity for diseased tissues?
bc it’s deposited in keratin precursor cells and gets tightly bound to new keratin - formed in area of fungal infection
**DDI concern of griseofulvin
INDUCES CYPS!!!!! decreased levels of warfarin and phenobarbital
AE griseofulvin
photosensitivity, rash, allergy
MOA terinafine
inhibits the fungal enzyme squalene epoxidase
this prevents the conversion of squalene to squalene 2,3-epoxide, leading to an accumulation of squalene.
NO PROPER ERGOSTEROL SYNTHESIS
FUNGICIDAL
terbinafine should not be given to which patients
hepatic and renal dysfunction
rifampin will ____ the levels of terbinafine
decrease
____ is a polyene macrolide like amphotericin B
nystatin
true or false
like amphotericin B, nystatin is also amphipathic
true
true or false
nystatin can be given orally
FALSE
cant be oral or parenteral - too toxic
true or false
nystatin is active against candida
true
which topical antifungal is less selective for fungal CYPS and is thus pretty toxic to humans and no longer used systemically?
ketoconazole
what was the first oral azole
ketoconazole
but not used orally anymore
uses for clotrimazole and miconazole
vulvovaginal candidiasis
oral thrush
dermatophytic infection
seborrheic dermatitis
clotrimazole and miconazole are used in which areas
skin and vagina
small amt of it will be absorbed – fungicidal for 2-3 days
efinazonazole is used for the topical treatment of _______
onychomycoses (fungal infection of nail bed)
AE efinaconazole
ingrown toenails, dermatitis, pain
MOA of ciclopirox
inhibits metal-dependent enzymes that are responsible for degrading peroxides in the fungus cell.
does this by chelating the di and tri valent cations (metals) necessary for these enzymes to work
disrupts the fungal cell membrane
MOA tolnaftate
inhibits squalene epoxidase in ergosterol synthesis
tolnaftate is INEFFECTIVE against _______
candida
tavaborole MOA
inhibits protein synthesis by inhibiting tRNA synthase
what molecule is present in fungal cell membranes but NOT in animal cell membranes
ergosterol
which antifungal drug inhibits microtubules
griseofulvin
miconazole MOA
inhibits ergosterol synthesis by inhibiting 14a-sterol demethylase
nystatin MOA
interferese with ergosterol function by binding ergosterol (same as amphotericin b)
Terbinafine MOA
inhibits squalene epoxidase
amphotercin B MOA
inhibits ergosterol function by binding to it (same as nystatin)
flucytosine MOA
inhibits thymidylate synthesis, interfering with DNA production
this antifungal is broad spectrum drug of choice for nearly all life threatening mycotic infections
amphotercin B
2 toxic pieces of amphotericin B
-shock like fall in BP during IV infusion
-renal toxicity (dose dep and may be severe)
amphotercin B toxicity seems to be lower with the ____ formulaiton of the drug
lipid
true or false
metabolic alkalosis and decrease in body temp are common AE of amphotercin B
no - they’re not
true or false
flucyostine works by inhibiting fungal DNA synthesis
true
MOA azoles
inhibit the conversion of lanosterol to ergosterol
MOA terbenifine
inhibit conversion squalene to lanosterol
true or false
there is no antifungal drug that inhibits squalene synthesis
true
azoles inhibit the conversion of ___ to ___
lanosterol to ergosterol
formation of artifical pores in the fungal membrane
amphotericin B
Antifungal drug that causes renal toxicity
amphotericin B
