Mycotic Drugs

The following categories are present for mycotic drugs:

• Polyenes (e.g: Amp B, nystatin)

  • Act on sterol synthesis in cell membrane (i.e.: Amp B forms channel whereby ion equilibrium is lost) – kills fungi

• 5-fluorocytosine

  • narrow spectrum of antifungal activity, and induces resistance quite rapidly

  • inhibits RNA and DNA synthesis (for details refer to Pg 561 Murray 3^rd Ed)

Azole derivatives (e.g: fluconazole, itraconazole, - systemic)

• • Broad spectrum activity against fungi, also have activity against gram positive bacteria

  • Act on cell membrane synthesis: act by inhibiting sterol synthesis (no cell membrane – cell dies)

• Griseofulvin

  • Acts on tubulin function, therefore cell wall integrity lost – cell dies (only used against dermatophyte infections – part of the moulds category of fungi – filamentous fungi)

• Terbinafine

  • Affects sterols of cell membrane, expensive drug. Used for dermatophytes – also works for dimorphic fungi such as Candida spp).

Note: Function of these drugs must be known. Not individual function, but rather collective function of individual groupings must be known. Don’t waste time learning all the individual drug function, not examinable at this stage!

Category: Microbiology Notes