Pharmacology of Antifungals Flashcards
A patient is diagnosed with onychomycosis. What antifungal is indicated for treatment?
Terbinafine
What ADRs are associated with Voriconazole?
Vision disturbances, hallucinations, phototoxicity, squamous cell carcinoma
What antifungal targets microtubules to inhibit mitosis?
Griseofulvin - also binds to keratin to prevent new infections
What ADR is associated with Fluconzole?
QT prolongation
What are the clinical indications for Grisefulvin?
Tinea capitis
What are the PK of Grisefulvin?
PO administration, metabolized by the liver
What is the MOA of Terbinaafine?
Inhibits the squalene epoxidase, which is toxic to fungi.
What is the primary administration for Ketoconazole?
Topical use for tinea infections and dermatophytosis
What are the indications for Itraconazole?
Dimorphic fungi, histoplasmosis, resistant fungi
What are the indications for Posaconazole?
mucormycosis, esophageal candidiasis with resistance to other azoles, prophylaxis for invasive fungi
What are the common Polyenes?
Nystatin, Amphotericin B
Terbinafine is generally prescribed PO, but can be used as a topical cream to treat what diseases?
Tinea corporis, tinea pedis
Myelosuppression and sterility are associated with what antifungal?
Flucytosine
What adverse reaction is associated with Nystatin?
GI Disturbance
What antifungal drug classes target ergosterol in the fungal cell membrane?
Allylamines, Polyenes, Azoles
What ADRs are associated with Grisefulvin?
Disulfiram-like reaction with alcohol use
Fluconazole is known to interact with what drug?
Warfarin - causes increased bioavailability
A patient is diagnosed with refractory aspergillosis. What antifungal is indicated for treatment?
Capsofungin
What is the preferred therapy for candidia albicans?
Fluconazole
How is Amphotericin B excreted?
By the kidneys in urine
What is the MOA for Echinocandins?
Inhibits the glucan synthase to disrupt the fungal cell wall
What ADR is associated with Micafungin?
Histamine release
True/False. Nystatin via IV is indicated for the treatment of oral thrush.
False. Nystatin is the DOC for oral thrush, but should never be administered via IV. It is too toxic
What is the MOA of Flucytosine?
A thymine analog that is integrated into fungal DNA and inhibits synthesis
What antifungals belong to the Echinocandin class?
Capsofungin, Micafungin, Anidulafungin
What antifungal is used as a stepdown from Amphotericin B treatment?
Posaconazole
What is the MOA of Azoles?
Inhibits ergosterol synthesis by blocking demethylation
Azoles are known to interact with what drugs?
Human liver enzymes
What is Naftifine?
A triple-action topical cream that is anti-bacterial, anti-fungal, and anti-inflammatory
When is Voriconazole indicated?
Fluconazole-resistant species, yeast, mold
When is Flucytosine indicated?
Serious fungal infections in combination with Amphotericin B
Nystatin is the drug of choice to treat what pathologies?
Oral thursh & diaper rash
What ADRs are associated with Amphotericin B?
Nephrotoxicity, anemia, infusion reactions
What drugs should not be combined with Itraconazole?
Statins
All Azoles are metabolized by the liver with one exception. What is the exception?
Fluconazole - metabolized by the kidneys and excreted in urine
What antifungal is used to treat critically ill neutropenic patients?
Micafungin
When is Amphotericin B indicated?
Serious life-threatening systemic fungal infections
What ADRs are associated with Ketoconazole?
Hepatotoxicity, QT prolongation
What is the MOA of Nystatin & Amphotericin B?
Forms micropores by binding to ergosterol that leads to cell lysis and death
How is Flucytosine excreted?
By kidney in urine
What antifungal is used as a prophalyxis for immunocompromised patients?
Fluconazole
What ADR is associated with Itraconazole?
Nausea
What ADRs are associated with Isavuconazole?
Constipation, hyperkalemia
What antifungals are most commonly used for superficial mycoses, such as athlete’s foot?
Miconazole & Clotrimazole