Anti-fungals Flashcards
Can you treat a fungal infection with an antibiotic?
No
what is the 4th cause of septicemia?
fungal infections (typically in immunosupressed patients)
WHat are the three groups of fungi?
Molds
True yeast
yeast-like fungi
what is a systemic infection with a mold?
Disseminated aspergillosis
what is the most “drying” of a prep? what is the least?
Gel is most (best for hairy areas)
Ointment is least
should powders be the only treatment of a fungal infection?
No, should be for additive (prevention)
how long are treatments for antifungals?
Weeks to months
What are three main antifungals?
Polyene Antibiotics
Imidazole antifungals
Triazole antifungals
What are 4 polyene antibiotics?
Amphotericin B
Nystatin
Flucytosine
Griseofulvin
What is the MOA of polyene antibiotics?
Bind to ergosterol in fungal cell membranes are form pore –> leak “-cidal”
is resistance a problem in antifungals?
Not as much as with antibiotics
what forms is amphotericin B available in? what form is less toxic?
IV
Liposomal preps are less toxic
What is the route for Nystatin ?
Cream, vaginal troches, suspension to oral mucosa
What Polyene would you use for severe systemic fungal infections?
Amphotericin B
What is nystatin mainly used to suppress?
Candidiasis on the skin and mouth
What are ADRs of amphoB?
hypotension
anemia (reversible)
nephrotoxicity (liposomal lessens this)
thrombophelbitis
What are ADRs of nystatin
N/V/D especially if swallowed
What is flucytosine used for?
Sytemic candidiasis
Cryptococcus meningitis
in combo w/ AmphoB
How is flucytosine administered?
Oral
has bad side effects of N/V
What type antifungal is griseofulvin?
“-static_
Where does griseofulvin concentrate?
Nails
Who can you use griseofulvin for?
Children
WHat is the drug of choice for nail fungal infections?
Terbinafine
What is a concern with griseofulvin?
P450 inducer (barbiturates, warfarin, oral contraceptives)
increase absorption with high fat meal (more side effects)
potentiates effects of alcohol
What is a broad spectrum antifungal that doesn’t cover aspergillus?
Ketoconazole
can see -cidial activity with higher doses
Are most fungal medications “static” or “cidial”
static
What can ketoconazole decrease in terms of steroid levels?
Decreased testosterone and cortisol production
how is ketoconzaole administered? What does it require to be dissolved?
PO
gastric acid for dissolution
Does ketoconazole enter teh CSF?
NO
Is ketoconazole teratogenic?
Yes because of endocrine effects
Ketoconzaole is an inhibitor of what?
P450
Do ketoconazole or amphoB have more restiatnce?
ketoconazole
What are 2 drugs that are only topical but are similar to ketoconazole?
Clotrimazole
Miconazole
Topical miconazole is a potent inhibitor of what?
Warfarin metabolism
What is a benefit of fluconazole?
Lacks endocrine side effects as seen with ketoconazole
can penetrate CSF
What is fluconazole a DOC for?
cryptococcus neoformans
candidemia
Coccidiodomycosis
Mucocutaneous candidasis
What is fluconazole a inhibitor of?
CYP3A4
CYP2C9
Can fluconazole be administered to a preggo patient?
No, it is a teratogen
What is a benefit of itraconazole
Cover aspergillis
no endocrine side effects
What is a concernign side effect of itaconazole?
hypokalemia
What is a “bigger gun” that is used for aspergillosis and serious infections?
Voriconazole
What is a big ADR of voriconazole?
Visual disturbances
What is an antifungal that isn’t avaliable as a tablet. Has aspergillis. More sucessful in immunocomprimised patients.
Posaconazole
What is a “-cidial” anti fungal that is sipophilic- so it penetrates superficial tissues well. first line agent for nail infections.
Terbinafine (Lamisil)
What is the main ADR you should monitor for terbenafine?
LFT’s and CBC
has had steven johnson rash
What is a second line therapy for those who have failed amphoB or itraconazole? Limited to aspergillus and candida species.
Caspofungin
What is used for esophageal candidiasis and prophylaxis for those undergoing stem cell transplant?
Micfungin
