Anti-fungals

Question 1

Clotrimazole

Answer 1

Fungal ianosine demethyl inhibitor

Broad spectrum of antimycotic activity, with its primary action against dividing and growing organisms.
Its mechanism of action is via via the inhibition yeast 14- alpha demythlase, a cytochrome P-450 enzyme that converts lanosterol to ergosterol, an important component of fungal cell membranes. This inhibition leads to increased membrane permeability and possibly disruption of membrane bound enzymes. It could act via inhibiting-
1. The endogenous respiration
2. The transformation of yeasts to mycelial forms
3. Triglyceride and/or phospholipid biosynthesis
4. The movement of calcium and potassium ions
across the cell membrane by blocking the ion transport pathway known as the Gardos channel

Question 2

Fluconazole

Answer 2

Fungal ianosine demethylase inhibitor

Inhibition of 14-alpha demethylase, a cytochrome P-450 enzyme that converts lanosterol to ergosterol (important component of fungal cell membrane)
This inhibition leads to increased membrane permeability and possibly disruption of membrane bound enzymes
It could act by
1. Endogenous respiration
2. Transpormation of yeasts to mycelial forms
Triglycerides and or phospholipid biosynthesis

Synthetic antifungal agent used to treat vaginal candidiasis

Question 3

Nystatin

Answer 3

Ionophore

Binds to ergosterol in fungal cell membranes
Binding of ergosterol causes formation of pores in the membrane leading to potassium and other cellular constituents leakage causing cell death

Anti-fungal therapy effective against a wide variety of
yeasts and yeast like fungi (candida albacins, C. parapsilosis, C. tropicali, C. guillermondi, C. pseudotropicalis , C. krusei, Torulopsis glabrata, Tricophyton rubrum, T. mentagrophytes

Question 4

Amphotercin

Answer 4

Ionophore

Binding of ergosterol in fungal cell membranes
This binding to ergosterol causes the formation of pores in the membrane, leading to potassium and other cellular constituents leakage causing cell death

Effective in vitro against many species of fungi (histoplasma capsulatum, coccidioides immitis, candida species, Blastomyces dermatitidis, rhodotorula, cryptococcus neoformans, sporothrix schenckii, mucor mucedo and aspergillus fumigatus

Question 5

Griseofulvin

Answer 5

Fungal mitosis inhibitor

Mycotoxic metabolic product of penicillium spp with in
vitro activity against various species of microsporum epidermophton and trichophyton. Mechanism of action is
1. Inhibits funfal cell mitosis and nuclear acid synthesis
2. Bind to and inhibit with the function of spindle and cytoplasmic microtubules by binding to alpha and beta tubulin
3. Bind to keratin in human cells, once the keratin- griseofulvin complex reaches the fungal site of action, it binds to fungal microtubules altering fungal mitosis

Fungal infections of nails and skin when antifungal
creams have not worked. Taken orally