Antifungals Flashcards
How does Ampho B work?
Binds ergosterol (unique to fungi) and forms membrane pores that allow leakage of electrolytes
What are the AEs of Ampho B?
Fever/chills (shake and bake)
hypotension
nephrotoxicity
arrhthymias
anemia
IV phlebitis
How can Ampho B toxicity be limited?
liposomal formulation
How does Nystatin work?
Same as ampho B, but can only be given topically
What are the main uses for Nystatin?
Thrush (candida) and topical for diaper rash or vaginal candidiasis
How does Flucytosine work?
Inhibits DNA and RNA biosynthesis by conversion to 5-FU by cytosine deaminase
AEs of Flucytosine?
Bone marrow suppression
How do AZOLES work?
Inhibit fungal sterol synthesis (14a…)
What is a major use of Fluconazole?
chronic suppression of cryptococcal meningitis in AIDs pts. and candidal infections of all types
How do Terbinafines work?
Inhibits fungal enzymes squalene epoxidase (good for dermatophytes especially onychomycosis)
How do echinocandins work?
Inhibit cell wall synthesis by inhibiting synthesis of B-glucan (invasive aspergillosis, Candida)
may cause GI upset and flushing via histamine release
How does Griseofulvin work?
Interferes with microtubule function; disrupts mitosis
Deposits in keratin-containing tissues (e.g. nails)
What is the preferred tx of toxoplasmosis?
Pyrimethamine
What is the preferred tx of trypanosoma brucei?
Suramin and melarsoprol
What is the preferred tx of trypanosoma cruzi?
Nifurtimox
What is the preferred tx of Leischmaniasis?
Sodium stibogluconate
How does Chloroquine work?
Blocks detox of heme into hemozoin causing heme to accumulate and be toxic to plasmodia. for use in tx of plasmodial species other thn P. falciparum (resistance too high)
How should P. faricparum be tx?
artemether/lumefantrine or atovaquone/proguanil or quinidine for life-threatening malaria
What are the AEs of Chloroquine?
Retinopathy
pruritis (esp. in black pts.)
