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

2020
Views:

134

Pages:

1
Author:

Charlee Buchanan

5.1 – “Bio 1101 01 meets Music 101”: amphotericin, fflucytosine, lucytosine, nystat nystatin in • Amphotericin (amphibians with fungi) o Ergosterol found in fungal cell membranes (compared to human & bacterial cholesterol) (“non-sterol” sign). Amphotericin forms pores in ergosterol cell wall allowing leakage of cell electrolytes & macromolecules and eventual cell death (frog aquarium has holes and amphibians are escaping). o Resistance evolves when structure of ergosterol involves changing molecular components of membrane (e.g. ↓ergosterol) o Amphotericin B has the broadest spectrum of action of the antifungals. Used for severe systemic or life-threatening fungal infections (body model with exposed organs). o Generally administered IV (ivy in terrarium). Given as a liposome, because of the high toxicity of the drug (liposome shaped frog). o For CNS infections, administered intrathecally (frog tongue looks like intrathecal line). Used to treat cryptococcal meningitis, often in conjugation with flucytosine (Anthony & Cleopatra, Act V: The Crypt). o Toxicities ▪ All result from amphotericin binding to mammalian cholesterol instead of ergosterol (frog binding to cholesterol themed necktie) ▪ Infusion related immediate reactions • Nearly universal • Fever, chills (“shake & bake”), spasms, vomiting, headache, hypotension, fainting (baking frog; fainting from frog on tie) • Thrombophlebitis at injection site (blue veiny frogs) ▪ Slow cumulative toxicities • Renal damage is most significant. Occurs in nearly all patients. (chemist) o Reversible prerenal azotemia o Irreversible tubular injury (Type 1 RTA) (graduated cylinder shaped like 1 filled with acid). Associated with hypokalemia (banana peel) o Renal magnesium wasting (falling magnets) o Usually have volume expansion with IV normal saline prior to amphotericin administration to help prevent renal damage (emergency saline wash). o Anemia d/t ↓EPO production (drained kidney scaring off white frog; broken tubules) ▪ Intrathecal administration • Seizures and major neuro damage (seizure lines) • Flucytosine o Flucytosine starts as a fluorinated cysteine. Converted by cytosine deaminase into 5-FU (Music C knocked over to U). o Halts fungal DNA & RNA synthesis (DNA and RNA like music on chalkboard being smeared by frog). • Nystatin o Forms pores in ergosterol cell wall allowing leakage of cell electrolytes & macromolecules and eventual cell death (frog aquarium has holes and amphibians are escaping; “Be Nyce” sign) o Active against most candida spp. (Canada flag with snow) o Topical Treats mucocutaneous candidiasis, including vaginal (snowball to the crotch) o Nystatin rinse for oropharyngeal candidiasis (drinking fountain). Esophageal candidiasis treated by systemics.