University:
University of North Carolina at Chapel Hill
Course:
NURS 312 | Pharmacology
Academic year:

2020
Views:

203

Pages:

1
Author:

sonalhava9qv

5.2 – “We’re n not ot in Candida A Anymore”: nymore”: az azole ole antifunga antifungals ls • Azoles include the imidazoles: ketoconazole, miconazole, clotrimazole; & triazoles: itraconazole, fluconazole, and voriconazole. Spectrum of actions broad. • MOA: ergosterol forms fungal membrane (emerald ergosterol blocks; postmodern fungus). Synthesized from lanosterol (munchkin builders inhibited by crushing house; “Lane Closed”). Azoles halt fungal CYP450 that synthesizes ergosterol (crushed car) o All are prone to drug interactions d/t effects on mammalian CYP450. • Voriconazole (car crushing vortex) o Preferred for invasive aspergillosis (aspirating scarecrow with lung hyphae) o Excellent treatment for candida, including candida esophagitis (Canadian flag). o Adverse effects ▪ Blurry vision or flashes of light, changes to color vision, usually transient (blurry flashes of light in tornado; sepia tones) ▪ Particularly potent inhibitor of mammalian CYP450. Dose reduction of many CYP450 substrates (including cyclosporine, tacrolimus, statins) required on initiation of therapy • Fluconazole (flying monkeys) o Used to treat mucocutaneous candida (yeasty snow). Given in a 1-time dose to treat vaginal candidiasis (crotch monkey). o Systemic fluconazole treats candida stomatitis & esophagitis in which case it’s given IV (esophagus like gutter snow) o Treats cryptococcal meningitis for lifelong maintenance (crypt with permanent monkey statues) o High levels of CNS penetration (meningitis mohawk helmets). Works some against dimorphic fungi but not drug of choice, but mainly against monomorphic. • Itraconazole (good witch) o Systemic infections with dimorphic fungi (e.g. histoplasmosis, blastomycosis, coccidioidomycosis, Sporothrix) (dimorphic butterflies) – “itraconazole for fungi with two iterations” o Used for onychomycosis & dermatophytosis (ruby slippers with tarnished toes) • Topicals, often miconazole or clotrimazole (“My cone” & close trim) o Tinea (tin man with ring-like rust rash) o Vaginal candidiasis (snowball to the crotch) • Ketoconazole (tin man’s key) o Cream form to treat cutaneous dermatophytosis o Other agents have a much better safety profile when administered systemically, as ketoconazole has a greater affinity for the mammalian CYP450. o Inhibits overproduction of cortisol in Cushing’s syndrome (moon face). May be used o Adverse effects ▪ Inhibition of cholesterol hormones (adrenal & sex hormones) by inhibiting 12,20-desmolase & 17-α-hydroxylase (first step of steroid synthesis from cholesterol) (key “locking” the adrenal gland shaped lock; moon face, M & F symbols. Witch synthesizing) ▪ Antiandrogenic Adverse effects, including gynecomastia, d/t inhibition of 17,20-lyase involved in synthesis of androgens