antifungal agents, targets, and resistance Flashcards
treatment with antifungals that are used to treat fungal infections most are __
fungistatic
what are the four major classes of antifungals
allylamines
azoles
polyenes
(echinocandins)
what class are the chitin synthase inhibitors
nikkomycins
what are the three uncategorized antifungals
griseofulvin
flucytosine
iodides
what is the mechanism of action for allyamines?
-inhibits squalene epoxidase
-block ergosterol synthesis
what are the potential side effects of allyamines?
GI +/- skin disease
what are the two members/examples of allyamines
naftitine
terbinafine
what is the route of application of naftitine
topical
what is the route of application of terbinafine
topical or systemic
are allylamines broad or narrow spectrum antifungals
broad spectrum
what allows terbinafine to concentrate in dermis/epidermis, adipose tissue, hair and nails
lipophilic properties
what are the two groups of azoles that have fungistatic compounds
imidazoles
triazoles
are imidazole and triazoles broad or narrow spectrum
broad spectrum
what is the mechanism of action for azoles?
-inhibit sterol 14-a demethylase
-block ergosterol synthesis
what is contraindication for azoles
in pregnant animals because antifungal has teratogenic potential
ketoconazole and miconazole are apart of what azole group
imidazoles
fluconazole and itraconazole are apart of what azole group
triazoles
what are the potential side effects of azoles?
steroid alterations
what is the mechanism of action of polyenes?
binds ergosterol
what is the route of infection for polyenes
systemic
are polyenes broad or narrow spectrum
broad
what are the potential side effects of polyenes?
nephrotoxicity
are nikkimycins broad or narrow spectrum?
narrow
what is the mechanism of action for griseofulvin?
block microtubules formation
what is the route of application for griseofulvin?
systemic
are griseofulvin broad or narrow spectrum?
broad
what are the potential side effects of griseofulvin?
teratogenic
what is the mechanism of action fluorinated pyrimidines?
RNA miscoding
what is the route of application for fluorinated pyrimidines?
systemic
is fluorinated pyrimidines broad or narrow spectrum
narrow
what are the potential side effects of fluorinated pyrimidines?
liver/hematology
what is the mechanism of action for iodides
block fungal metabolism
what is the route of application for iodides
systemic
are iodides broad or narrow spectrum
narrow
what are the potential side effects of iodides?
iodism
how should sodium iodide be administered?
IV
how should potassium iodide be administered?
oral (NEVER IV)
what are nikkomycins effect against?
cryptococcus and other dimorphic fungi
what is an example of a polyenes?
amphotericin B
What antifungal binds to sterols like ergosterol, though may also bind sterols
present in the cell membranes of the renal tubules, leading to nephrotoxicity?
amphoteracin B
What is the mechanism of action of allylamine antifungals like Terbinafine?
Inhibition of ergosterol synthesis via binding squalene epoxidase
Flucytosine is able to affect protein synthesis through its action as a:
Pyrimidine analog drug
what are the factors that influence a successful antifungals therapy outcome
what factors might result in a failure of antifungal therapy?
