Antifungals Answers – Flashcards

1. binds ergosterol leading to pore formation and leakage of cellular contents (electrolytes)

2. Clinical use- systemic mycoses: cryptococcus, blastomyces, coccidioides, aspergillus, histoplasma, candida, mucor

3. Not absorbed orally- intrathecally for fungal meningitis (does not cross BBB)

4. Toxicity- fever/chills, hypotension, nephrotoxicity (reduced with hydration), arrythmias, anemia, IV phlebitis

5. Liposomal amphotericin reduces toxicity

6. Analgesics to alleviate infusion-related probs

7. Primary resistance unusual- fusarium, scedosporium, lusitaniae, guilliermondi

1. Polyene antifungal with anti-candida activity

2. Binds ergosterol disrupting funal membranes- toxic for systemic use

2. oral solution swished and swallowed for oral candidiasis, topical for diaper rash or vaginal candidiasis

1.Fluconazole, ketoconazole, clotrimazole, miconazole, itraconazole, voriconazole

2. Inhibit fungal sterol (ergosterol) synthesis- inhibit sterol 14-alpha-demethylase leading to accumulation of 14-alpha-methylsterols and disrupting acyl chains

3. Used in systemic mycoses- fluconazole for cryptococcal meningitis in AIDS and all candidal infections; ketoconazole for blasto, coccidio, histo and candida albicans; clotrimazole and miconazole for topical fungal infections

4. Toxicity: gynecomastia by inhibiting hormone synthesis, liver dysfunction (inh P-450), fever, chills

1. Fluorinated pyrimidine with antimetabolite fx (deaminated to form 5-FU then converted to 5-FUMP which may be phos and incorporated causing miscoding or 5-FdUMP which is a potent inhibitor of thymidylate synthase)

2. Combined with Amp B for cryptococcus meningitis and other systemic fungal infections

3. primary resistance may occur with candida, C. neoformans and aspergillus due to altered cytosine permease

4. Secondary resistance almost alwasy develops when tx C. neoformans/candida w monotherapy

1. Only pneumocandin/echinocandin in US

2. inhibits beta-(1,3)-D-glucan synthase thus inhibiting cell wall synthesis

3. Used in invasive aspergillosis

4. Hypokalemia, GI upset, Histamine release (flushing), phlebitis

5. R due to alterations in Beta-(1,3)-glucan synthase binding target

1. Allylamine antifungal- Blocks squalene epoxidase inhibiting the formation of ergosterol

2. used to treat dermatophytoses (especially onychomycosis)

3. Toxicity- hepatotoxicity, neutropenia, TEN, steven-johnson syndrome

1. Binds to fungal polymerized MT leading to inhibition of fungal mitosis

2. Deposits in keratin-containing tissues (e.g. nails)

3. Used in oral treamnt of superficial infections- inhibits growth of dermatophytes (tinea, ringworm)

4. Toxicity- teratogenic, carcinogenic, confusion, HA

4. induce metabolism of warfarin and OC (P-450)

1. Anti-Candida and dermatophyte activity

2. Almost no cutaneous toxicity

3. pyridone

1. Haloprogin

2. tinea vesicolor, candida, dermatophytes

3. skin irritation and exacerbation of lesions

1. dermatophytes

2. less effective than miconazole for tinea pedis