Antifungal and Antiparasitic Therapy Flashcards
What is the mechanism of action of Amphotericin and Nystatin?
Bind to ergosterol in cell membrane, disrupt cell wall permeability, resulting in cell death.
What is the nickname of Amphotericin, and why is this so?
- “Amphoterrible”
2. It’s toxicity (nephro)
Amphotericin and Nystatin are:
A) Fungistatic
B) Fungicidal
B
What is the spectrum of Amphotericin B IV?
- Candida
- Coccidioides
- Cryptococcus
- Blastomyces
- Histoplasma
What are the clinical indications for Amphotericin B IV?
- Aspergillus
- Cryptococcal meningitis
- Blastomycosis
- Coccidiomycosis
- Not 1st line for Candida
Nystatin is primarily used against what type of fungus? It is indicated for 2 conditions involving this pathogen.
- Candida
2. Oropharyngeal and vaginal candidiasis
The Azoles include: (4)
- Fluconazole
- Itraconazole
- Voriconazole
- Posaconazole
What is the MOA of the Azoles?
They inhibit lanosterol C14-demethylase to inhibit ergosterol synthesis
Azoles are “BLANK” against Candida, and “BLANK” against Aspergillus
- Fungistatic
2. Fungicidal
Which 2 Azoles have excellent bioavailability?
- Voriconazole
2. Fluconazole
What is one potential downside to the Azoles?
They are potent CYP 3A4 inhibitors
What is the spectrum of Fluconazole (IV/PO)
- Candida
- Coccidioides
- Blastomyces
- Histoplasma
What are the clinical indications for Fluconazole?
- Invasive C. albicans
- Esophageal candidiasis
- Severe mucocutaneous candidiasis
- Oral stepdown for cryptococcal meningitis
What is the spectrum of Itraconazole PO?
- Candida
- Aspergillus
- Coccidioides
- Cryptococcus
- Blastomyces
- Histoplasma
What are the clinical indications for Itraconazole PO?
- Oral stepdown for coccidiomycosis
- Blastomycosis
- Histoplasmosis
- Alternative for Candida and Aspergillus (but has poor oral absorption)
What is the spectrum of activity for Voriconazole (IV/PO)?
- Candida
- Aspergillus
- Coccidioides
- Cryptococcus
- Blastomyces
- Histoplasma
- Fusarium
- Scedosporium
What are the clinical indications for Voriconazole (IV/PO)?
- Aspergillus
- Fusarium
- Scedosporium
- Drug resistant fungal infections
What is the spectrum of Posaconazole PO?
- Candida
- Aspergillus
- Coccidioides
- Cryptococcus
- Blastomycosis
- Histoplasma
- Fusarium
- Scedosporium
- Zygomycetes
What are the clinical indications for Posaconazole PO?
- Zygomycetes
- Fusarium
- Scedosporium
- Drug resistant fungal infections (broad spectrum)
What 3 agents are considered Echinocandins?
- Anidulafungin
- Caspofungin
- Micafungin
What is the MOA of the Echinocandins?
They inhibit the production of B-(1,3)-D-glucan, needed for cell wall synthesis
Echinoderms are orally absorbed, T or F?
False. IV only.
All Echinocandins presented in class are given IV only? T or F
True.
What is the spectrum of the Echinocandins?
- Candida
2. Aspergillus
What are the clinical indications for the Echinocandins?
- Serious non-albicans Candida infections
2. Active against Aspergillus (studied in salvage therapy)
What 4 agents are topical antifungals?
- Clotrimazole
- Ciclopirox
- Tolnaftate
- Terbinafine
What is the spectrum of Clotrimazole cream?
- Trichophyton
- Microsporum
- Epidermophyton
- Candida
- Malassezia furfur
What are the clinical indications for Clotrimazole cream?
- Tinea pedis
- Tinea cruris
- Tinea corporis
- Tinea versicolor
- Cutaneous candidiasis
What is the spectrum of Ciclopirox?
- Trichophyton
- Microsporum
- Epidermophyton
- Candida
- Malassezia furfur
What are the clinical indications for Ciclopirox?
- Mild onychomycosis
- Tinea pedis
- Tinea cruris
- Tinea corporis
- Cutaneous candidiasis
- Tinea versicolor
What is the spectrum of Tolnaftate?
- Trichophyton
- Microsporum
- Epidermophyton
- Malassezia furfur
Tolnaftate is not effective against which fungus?
Candida
What are the clinical indications for Tolnaftate?
- Tinea pedis
- Tinea cruris
- Tinea corporis
- Tinea versicolor
What is the spectrum of Terbinafine?
- Dermatophytes (Trichophyton, Microsporum, Epidermophyton)
What are the clinical indications for Terbinafine?
PO for Tinea capitis and onychomycosis
Topical: Tinea pedis, Tinea cruris, Tinea corporis, Tinea versicolor
These 6 agents are considered Antimalarial
- Chloroquine
- Mefloquine
- Atovaquone/proguanil
- Artesunate
- Quinine
- Primaquine
What are the clinical indications for Chloroquine?
- Malarial prophylaxis
2. Tx for chloroquine susceptible regions
What are the clinical indications for Mefloquine?
- Malaria prophylaxis for Chloroquine resistant regions or chloroquine intolerance.
What are the clinical indications for Atovaquone/proguanil?
- Malarial prophylaxis for chloroquine/mefloquine resistant regions or intolerance of these drugs
- 1st line for uncomplicated P. falciparum Tx
What antibiotic can be used as alternative malaria prophylaxis or adjunctive Tx?
Doxycycline
What are the clinical indications for Artesunate IV?
- Preferred Tx for severe malaria, followed by PO therapy.
What are the clinical indications for Quinine IV/PO?
- IV for 2nd line Tx of severe malaria (+ PO therapy)
2. PO 2nd line for uncomplicated malaria
What are the clinical indications for Primaquine?
- Terminal prophylaxis for P. ovale, P. vivax; primary prophylaxis
If you cannot use a 1st line PO med for malaria, what antibiotic can be used for combination malaria Tx?
Clindamycin
Why is Mefloquine not used for malarial Tx?
- At the high doses required for Tx it can cause neuropsychiatric effects
What are 2 contraindications for Primaquine?
- Pregnancy
2. G6PD deficiency
What 5 drugs are Antihelminthics?
- Albendazole
- Mebendazole
- Ivermectin
- Pyrantel pamoate
- Praziquantel
What are the clinical indications for Albendazole PO?
- Alternative for Strongyloidiasis, roundworm, pinworm, whipworm, hookworm
What are the clinical indications for Mebendazole PO?
- Roundworm, pinworm, whipworm, hookworm
What are the clinical indications for Ivermectin PO?
- Strongyloidiasis
2. Alternative for roundworm or whipworm
What are the clinical indications for Pyrantel pamoate PO?
- Pinworm
2. Hookworm
What are the clinical indications for Praziquantel PO?
Intestinal tapeworms
Which Antihelminthic agent can cause Mazzoti reaction?
Ivermectin
What is the Mazzoti reaction?
Host inflammatory reaction to death of parasites - fever, hives, asthma, GI upset
Ivermectin is not effective for?
Hookworm
Iodoquinol and Paromomycin are effective against what type of pathogens?
Protozoa
What are the clinical indications for Iodoquinol PO?
- Dientamoeba fragilis
- Amebiasis
- Alternative for Blastocystis
What are the clinical indications for Paromomycin PO?
- Alternative agent for Dientamoeba fragilis, amebiasis, giardiasis
Which antibiotic has activity against intestinal protozoa?
Metronidazole
What are the clinical indications for Permethrin (cream, lotion)?
- Scabies
2. Lice
Which 2 agents are considered Polyenes?
- Amphotericin
2. Nystatin