MEDICAL MYCOLOGY

Dr Tadayo Hashimoto M.D.
Professor
Department of Microbiology & Immunology

23. Flucytosine:

is effective against filamentous fungi
can not be administered orally
can be used without worrying about the development of resistance to the drug
is converted to 5-fluorouracil which can be incorporated into fungal RNA or serves as inhibitors of thymidylate synthetase
should not be used in combination with amphotericin B

(D) Flucytosine was originally developed as an anti-cancer drug. Its effectiveness is limited to certain yeast form fungi (Cryptococcus neoformans). This drug is usually given orally in combination with parenteral amphotericin B injection. This is because (1) these two drugs work synergistically, and (2) this minimizes the development of drug resistance by susceptible fungi. The drug works as an inhibitor of RNA and DNA synthesis as described in D. (Ryan et al, p. 583 this infection. (Joklik et al, pp. 1117-111; Ryan et al, pp. 614-615)

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Last Reviewed: Feb 11, 2009
Created: Aug 9, 1996