ID III: Antifungals, Antivirals, & Antiparasiticals Flashcards
Name the most common Candida sp.
c. albicans, c. tropicalis, c. glabrata, c. krusei
Name the most common yeast species
candida sp. and Cryptococcus neoformans
What is a dimorphic fungi?
Fungi that exists as a mold at lower temperatures and a yeast at higher temperatures.
“Mold in the cold, yeast in the heat”
Name the most common types of mold
Aspergillus sp. and zygomycetes (includes mucor sp. & rhizopus sp.)
Name the dimorphic fungi
histoplasma capsulatum, blastomuyces dermatitidis, and coccidiodes immitis
MOA of amphotericin B
Binds to ergosterol, altering the cell membrane permeability and causing cell death
*fungicidal
BBW and SE of ampho B
BBW: dosing based on specific product name and lipid-based form of ampho - use caution
SE: infusion related (fever, chills, HA, malaise, rigors, decreased K & Mg), nephrotoxicity
*Lipid formulations have decreased SE
Coverage of ampho B
yeasts, molds, and dimorphic fungi
Initial tx for INVASIVE fungal infxns - cryptococcal meningitis, histoplasmosis, and mucormycosis
MOA of flucytosine
penetrates fungal cells, converted to flurouracil - competes w/uracil and interferes w/fungal RNA and protein synthesis
*fungicidal
Coverage of flucytosine
Used with ampho B for invasive cryptococcal meningitis or candida infections
MOA of azole antifungals
Decrease ergosterol synthesis and inhibit cell membrane formation; also inhibitors fungal CYP450 system
*fungistatic, but can be fungicidal for some fungal pathogens
Coverage of fluconazole
yeasts: c. albicans, c. tropicalis, Cryptococcus
dimorphic fungi: coccidiodes
- limited efficacy against c. glabrata d/t resistance
- c. krusei is considered fluconazole-resistant
Brand name of fluconazole
Diflucan
Coverage of itraconazole
yeasts: c. albicans, c. tropicalis
dimorphic fungi
molds: Aspergillus
Brand name of itraconazole
Sporanox (capsule/tab), Onmel (solution)
SE of azole antifungals
increased LFTs, QT prolongation
CYP450 - especially CYP3A4 DDIs
Renal dosing of fluconazole
Requires dose adjustment
Counseling for itraconazole oral caps/tab vs. solution
Caps/tab: take with food
Solution: take without food
Coverage of voriconazole
Broad spectrum w/ better coverage of aspergillus sp., c. glabrata, and c. kruesi than itra/fluconazole.
- DOC for aspergillosis
- NO coverage against zygomycetes
Storage of voriconazole solution
Do NOT refrigerate
Brand name of voriconazole
Vfend
SE of voriconazole
Visual disturbances, increased LFTs and SCr, CNS toxicity (hallucinations, HA, dizziness), teratogen, QT prolongation (correct K, Ca, and Mg prior to initiating tx)
Monitoring of voriconazole
trough levels (1-5mcg/mL), visual fxn, LFTs, electrolytes
Renal dosing of voriconazole
Requires adjustment w/ IV d/t containing sulfobutyl either beta-cyclodextrin - which can accumulate in worsen renal fxn
Coverage of posaconazole
covers more resistant yeasts, and molds w/ activity against zygomycetes
Brand name of posaconazole
Noxafil
SE of posaconazole
QT prolongation (correct K, Ca, and Mg prior to initiating tx), increased LFTs, decreased K and Mg
Counseling with posaconazole
Suspension and tabs should be taken with food
Coverage of isavuconazonium
covers more resistant yeasts, and molds w/activity against zygomycetes
Brand name of isavuconazonium
Cresemba
Special administrations considerations with isavuconazonium
Requires a filter (0.2-1.2 microns) during administration
MOA of echinocandins
Inhibit the synthesis of beta(1,3)-D-glucan, an essential component of the cell wall
*fungicidal
Name the echinocandins
Caspofungin (Cancidas), Micafungin (Mycamine), Anidulafungin (Eraxis)
Renal dosing of echinocandins
Do not required dose adjustment
SE of echinocandins
increased LFTs, hypotension, fever, N/V/D, and decreased K and Mg
Coverage of echinocandins
Candida sp. including c. glabrata and c. krusei and non-albicans strains resistant to azole antifungals.
Activity against aspergillus, but should be used in combo
Hepatic impairment dosing of echinocandins
Caspofungin requires adjustment in moderate hepatic impairment
MOA of griseofulvin
Bind to the keratin precursor cells which prevents fungal invasion
Indications: dermatomycosis and tinea infections of skin, hair, and nails
Brand name of griseofulvin
Grifulvin V, Gris-PEG