Term
| fungal dz = 2 broad categories: |
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Definition
dermatophytes (skin)
internal dz (aspergillus) |
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| most antimycotics actions are... |
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| dermatophyte infections should be tx... |
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Definition
| ...systemically (topical tx is rarely sufficient) |
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| tx of yeast infections with... |
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| fungal sterol synth is imp for... |
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Definition
| ...mb integritiy and fluidity |
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| unique pathway antimycotics target = |
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Definition
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| give 2 examples of polyenes |
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Definition
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Definition
| ...colloid suspension or dissolved in mild detergent (as nearly water insoluble) |
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| polyene structure means its... |
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Definition
| ...amphipathic - hydrophobic and hydrophilic ends) |
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| polyene structure means its... |
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Definition
| ...amphipathic - hydrophobic and hydrophilic ends) |
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Definition
| Interacts with egosterol in call mb = forms a pore = allows ions through and leak ATP |
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| polyene absorption via gut = |
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Definition
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| tx of GI mycoses with polyenes admin... |
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Definition
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| systemic tx with polyenes admin... |
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Definition
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| plasma half life of poleyene = |
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Definition
| long as polyenesa re highly plasma bound (due to lipophilic nature of polyenes) |
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| clinical use of polyenes = |
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Definition
wide spectrum of activity including aspergillus and candida
for immunocompromised patients may need to give long term whuch may result in toxicity :( |
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Definition
slow toxicity, usually renal - tubular necrosis and renal failure
Infusion related fever but v rare |
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Definition
unclear
inhibits nucleic acid synth and mitosis and microtubule formation in some way |
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Term
| is griseofulvin water soluble? |
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Definition
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| is griseofulvin fat soluble? |
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Definition
| quite = absorption enahnced if given with fatty foods |
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Term
| griseofulvin is metab by... |
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Definition
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| griseofulvin distribution = |
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Definition
gd
depo in newly formed skin where it binds to keratin in the stratus corneum |
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Term
| linical use of griseofulvin |
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Definition
tx of dermatomycoses
skin becomes resisitant to further fungal growth and as new skin and hair grow and replace old the infection gradually disappears. takes ~6wks |
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Term
| if stop tx with griseofulvin b4 6wks= |
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Definition
| reinfection (as drug only fungistatic) |
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Definition
rare- relatively safe and qu commonly used
1.allergies
2.drug interactions eg with warfarin = decr anticoagulant effect
with phenobarbitone = incr griseofulvin metab
3. teratogenesis |
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Term
| Azoles, give three examples |
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Definition
ketoconazole
imidazole
triazole |
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Term
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Definition
| inhibit laosterol 14-demethylase synth by inhibiting cytochrome p450 = accum of lanosterol and decr ergosterol = change perm and fluidity of cells mb |
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Definition
| fungistatic excpet at high concnetrations |
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Definition
relatively non toxis :)
1. mainly GIT upsets (V and D)
2. ketoconazole effects mammalian cytochrom o450 (responisble for drug metab and steroid synth so ketoconazole can incr duration of other drugs) |
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Term
| ketonconazole can be used to tx |
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Definition
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Definition
-broad spectrum
-systemic or topically
useful in face of polyene resistance
not v effective against yeast |
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Term
| flucytosine works specifically against.. |
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Definition
| ...yeast (no fungi activity) |
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| flucystosine (5-FU) is an analogue of... |
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Definition
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Definition
taken up by yeast cells via cytosine permease (specific mech to yeast)
flucytosine is converted to 5-FU then fUMP then fUTP
fUMP inhibits RNA synth
fUTP inhibits DNA synth |
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Term
| flucytosine is synergistic with... |
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Definition
| ...amphotercin B (as amphotercin B incr cell perm = incr uptake of flucytosine) |
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Definition
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| distribution of flucytosine = |
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Definition
| widespread, goes into CSF = gd for intracranial infections |
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| resistance to flucytosine = |
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Definition
| rapid :( therfore give with amphotercin B |
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Term
| toxicity of flucytosine = |
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Definition
BM supression due to antineoplastic action of other metabolites of the drug (target rapidly dividing cells)=thrombocytopaenia, leukopaenia, anameia
overcome by lowing doses by co-admin with amphotericin B |
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