antifungal therapeutics Flashcards
drugs to use for thrush
- nystatin
- clotrimazole
- fluconazole
nystatin regimen for thrush
swish/swallow qid for 5-10 days
-avoid at meal times
clotrimazole regimen for thrush
dissolve 1 troche 5xday for 5-10 days
fluconazole regimen for thrush
200 mg once
or
100 mg qd for 7-14 days for mod-severe
options for fluconazole refractory thrush
itraconazole posoconazole voriconazole caspofungin AMB
chronic suppression for thrush regimen
fluconazole 100 mg 3 times per week
what to use for candidal esophagitis
systemic only
fluconazole 200-400 mg 7-10 days
what to use for relapse of candida esophagitis
fluconazole 400-800 mg for 14-21 days
main problem with AMB
nephrotoxicity
AMB covers what fungi
- candida
- aspergillus
- cryptococcus
- coccidioides
- histoplasma
- sporothrix
- mucor
AMB lipid formulations
- complexed with 2 lipid bilayer ribbons
- complexed with lipid vesicles
AMB dosing technique
- first do test does of 1 mg
- taper up to test the kidneys
AMB infusion reactions
bronchospasm dyspnea tachycardia fever chills rigors myalgia N/V
pretreat rigors with what
demerol
how does AMB cause renal failure
direct damage of distal tubules leading to waste of Na, K, and Mg, causing tubular acidosis
ways to reduce AMB renal toxicity
- monitor renal fxn
- avoid AMB if CrCl < 30
- QoD dosing
- lipid formulations
flucytosine use
only in combinations in serious infections to avoid resistance
flucytosine serious adverse effects
leukopenia
thrombocytopenia
flucytosine target concentration
under 100 mcg/ml
why isn’t ketoconazole used as much
many drug interactions
liver toxicity
fluconazole adverse effects
well tolerated
maybe n/v, LFTs
fluconazole spectrum
candida
crptococcus
itraconazole adverse effects
GI
headache
minor LFT elevation
hypokalemia
preferred dosage form for itraconazole
PO solution over the capsule
itraconazole solution counseling
take on an empty stomach for max absorption
itraconazole capsule counseling
take with food and acidic drink
voriconazole adverse effects
visual changes LFTs rash hallucinations QTc prolongation
screening before using voriconazole
EKG
CrCl
why don’t we give IV voriconazole or posaconazole when CrCl <50
solubilization agent (SBECD) can accumulate
voriconazole drug interactions
extensive, inhibiting metabolism
voriconazole dosing for invasive aspergillosis
6 mg/kg iv q12h for a day, then 4 mg/kg IV q12h
voriconazole IV dosing for candidemia
6 mg/kg iv q12h for a day, then 3 mg/kg IV q12h
voriconazole oral dosing for pt over 40 kg with candidemia
400 mg q12h for 1 day then 200 mg q 12h
voriconazole oral dosing for pt under 40 kg with candidemia
200 mg q12h for one day then 100 mg q12h
only azole with reliable activity vs zygomycetes
posaconazole
posaconazole indication
prophylaxis of invasive aspergillus and candida infections of immunocompromised pts
posaconazole dosage forms and their use
IV - prophylaxis of invasive infections
oral - prophylaxis of invasive infection
suspension - thrush
posaconazole adverse effects
n/v/d
rash
potential QT prolongation
posaconazole tablet dosing for prophylaxis
300 mg bid with fatty meal
isavuconazole indications
invasive aspergillosis and mucormycosis
isavuconazole dosing
372 mg q8h for 6 doses
isavuconazole side effects
LFT elevations skin reactions SJS n/v/d headache hypokalemia
caspofungin dosing
70 mg IV day 1, then 50 mg IV qd
caspofungin notable drug interactions
phenytoin, dexamethasone, carbamazepine, rifampin
caspofungin adverse effects
*uncommon* chills fever thrombophlebitis n/v
caspofungin main use
- febrile neutropenia when fluconazole can’t be used
- candidemia
- esophageal candidiasis when fluconazole can’t be used
assay that diagnoses aspergillosis
galactomannan assay
test that detects invasive fungal disease
B-D-glucan assay (Fungitell)
things that can cause Fungitell false positives
- hemodialysis w/ cellulose membranes
- platelet infusions with filters
- immune globulin infusion
- serious bacterial infection
- augmentin
- zosyn
when to treat asymptomatic cadiduria (UTI)
- patient is neutropenic
- patient is undergoing urologic procedure
drug to treat candiduria (UTI)
fluconazole (both asymptomatic and symptomatic)
symptoms of candiduria
dysuria
frequency
urgency
empiric therapy for candidemia
caspofungin 70 mg load, then 50 mg per day
fungus resistant to fluconazole
candida glabrata, candida krusei
alternate options for candidemia
micafungin
fluconazole
voriconazole
AMB
options for candidemia in a neutropenic host
caspofungin
lipid based AMB
fluconazole
voriconazole
how long to treat for candidemia in neutropenic host
2 weeks after last positive culture
what else to test for in candidemia
eye exam
how long to treat candidemia in non-neutropenic host
2 weeks after first negative blood culture
