Pharm - Antifungals Flashcards
“azoles” inhibit the enzyme ………………
“azoles” inhibit the enzyme 14-alpha-demethylase, the enzyme responsible for the last step in ergosterol synthesis.
Caspo “fungin” inhibits synthesis of …………
Caspo “fungin” inhibits synthesis of Beta-glucan(cell wall component)
Terbinafine inhibits ………………..
Terbinafine inhibits Squalene epoxidase, an enzyme upstream from the in the ergosterol synthesis pathway.
Amphotericin B(nystatin) mechanism of action?
Interact with ergosterol in fungal membranes to form artificial pores.
drug with the widest fungicidial spectrum?
Amphotericin B - interacts with ergosterol in the membrane. Resistant has been described in fungi with low ergosterol content in the membrane.
Amphotericin side effects?
renal toxicity, anaphylaxis
ketoconazole, fluconazole, Itraconazole, Voriconazole mechanism of action?
the “-azoles” inihibit 14-alpha-demethylase, the last step in ergosterol synthesis.
side effets of “-azoles”?
interfere with steroid synthesis
Which “-azole” is the DOC in immuno suppressed patients?
Fluconazole
side effects of “-azoles”?
lowered synthesis of steroids, including testosterone and cortisol = decreased libido, gynecomastia, menstrual irregularities.
the enzymes 11-hydroxylase and 21-hydroxylase, responsible for steroid synthesis are part of what group of enzymes?
P450
Flucytosine mechansim of action?
5FC mius NH2 group = 5FU(anticancer). 5FU is triphosphorylated and incorporated into fungal RNA
Flucytosine side effect?
toxic o bone marrow
Flucytosine syngergistic use?
coadministered with amphotericine B in severe cryptococcal and cadidal infctions
Griseosulvin distributes where …………… is found.
Griseosulvin distributes where keratin is found. Skin, hair and nails.
Caspofungin and Micafungin inhibits ……………
Caspofungin and Micafungin inhibits glucan synthesis
Amphotericin B absorption and administration?
Poor GI absorption. Administered IV for systemic infections
Amphotericin B side effects?
- chills
- fever
- impaired renal function
Imidazoles moa?
inhibits fungal P450 demethylation of lanosterol to ergosterol
Imidazoles adverse effects?
- interferes with steroid synthesis
- gastric upset
- toxicities
DOC for disseminated blastomycosis?
intrconazole
Miconazole areas of use?
applied topically
- ringworm
- Tinea pedis
- vulvovaginal candidasis
Nystatin moa?
like Amphoterecin B - pores in fungal cell wall
Nystatin route of administration?
too toxic for systemic use. Peroral or topical use only
Nystatin areas of use?
Candidasis in
- Skin
- Mucous membranes
- GI tract(NOT absorbed in GI)
Griseofulvin moa?
binds microtubules and prevents spindle formation and mitosis in fungi
Griseofulvin areas of distribution?
where keratin is found - hair, nails, and skin
Flucytocine moa?
converted to 5-fluorodeoxyuridylic acid which inhibits thymidilate sythase = in other words disrupted nucleic acid synthesis
Flucytocine adverse effects?
bone marrow suppression
Caspofungin area of use?
patients with severe aspergillosis
Trimethorim-sulfa is used to murder….
PCP(pneumocystitis jirovecci)
