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11 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Why individual is prevalent to fungal infections? |
1. Broad spectrum Antibiotics 2. Immunosuppressant Anticancer drugs 3. Indwelling catheters and implants 4. AIDS |
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Polyene Antibiotics 1. Amphotericin B (AMB) |
Obtained from Streptomyces nodusos |
Obtained? |
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Chemistry? |
Macrocyclic ring, conjugated dual bonds Highly lipophilic ,many -OH groups Carboxylic and polar amino sugar group on other end |
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Mechanism of action |
High affinity to Ergosterol Ergosterol + AMB = Micropore Micropore- ions, aminoacids move out Stabilized by membrane sterols Increase permeability of cell |
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Selectivity? |
AMB binds with cholesterol of host cell so low selective activity of Polyene antibiotics Have systemic toxicity |
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Spectrum: |
Candida albicans Histoplasma capsulatum Cryptococcus neoformans Fungicide at high conc Static at low |
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Resistance |
Rare in leucopenic cancer patients |
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Pharmacokinetics |
I.V as suspension made up of deoxycholate CSF penetration- low Half life - 15 hr , 60% liver metabolism |
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Adverse effects |
1.Acute- Nausea, vomiting, fever, pain ,aches Due to release of TGF alpha and IL 2. Long term - @ CAN A. CNS toxicity- intrathecal injection B. Anaemia- bone marrow depression C . Nephrotoxicity- ( Acidosis,Hypokalemia, inability to concentrate urine) |
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Uses |
Oral , vaginal or cutaneous candidiasis Febrile Neutropenia Leishmaniasis- Mucocutaneous leishmania |
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Interaction |
Flucytosine + AMB = supra additive action Aminoglycosides, vancomycin, cyclosporin. + AMB = increase nephro toxicity |
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