Ancobon - Flucytosine

Griseofulvin (Grisactin) exerts its effect by being deposited in keratin precursor cells, which are then gradually lost (due to the constant shedding of top skin cells), and replaced by new, noninfected cells. The mode of action of flucytosine (Ancobon) is not clearly understood. Clotrimazole (Lotrimin, Mycelex) binds with phospholipids in the fungal cell membrane,... 

Flucytosine is used with amphotericin for treating certain systemic fungal infections, in particular for treating subcutaneous chromobastomycosis. It is used intensively for treating systemic infections of the urinary tract that are caused by various strains of Candida. Synonyms of this drag are ancobon, ancotil, and others. 

Flucytosine (Ancobon) possesses clinically useful activity against Cryptococcus neoformans, Candida species, Torulopsis glabrata, and the agents of chromomycosis. Susceptible fungi deam-inate flucytosine to 5-fluorouracil, which becomes an antimetabolite. Flucytosine, which is excreted by the kidney, should be used cautiously in the setting of renal impairment. Flucytosine is a bone marrow depressant. Flucytosine is used in combination with amphotericin B. 

Flucytosine, USP. 5-Fluonx ytosine. 5-FC. 4-amino-3-lluoro-2( l//)-pyrimidinone. 2-hydroxy-4-amiiio-5-fluoro-pyriiniditie (Ancobon). S-Fluorocytosine is an orally active mlifungal agent with a very narrow spectrum of activity. It is indicated only for the treatment of seriou.s systemic infections caused by susceptible strains of Caiutida and Cryp-Uicomis. spp. 

Flucytosine (ancobon) is clinically useful for Cryptococcus neoformans, Candida spp., and chromoblastomycosis. It is given orally at 100 mgAg/day, in divided doses at 6-hour intervals and is used predominantly in combination with amphotericin B. An all-oral regimen of flucytosine plus fluconazole has been advocated for therapy of AIDS patients with cryptococcosis, but the combination has substantial Gl toxicity without evidence that flucytosine improves the outcome. The combination of flucytosine with C-AMB runs the risk of substantial bone marrow suppression or colitis if the flucytosine dose is not promptly adjusted downward if amphotericin B—induced azotemia occurs. It is common practice in HIV-negative patients with cryptococcal meningitis to begin with C-AMB or ambisome plus flucytosine and change to fluconazole after the patient has improved. 

Ancobon Capsules (Flucytosine). ICN Fharmaceuticals Inc. US Prescribing infonnation, March 2003. 

Flucytosine 4.23) (5-fluorocytosine, Ancobon ) has proved clinically successful as an orally active fungicide for treating such systemic diseases as candidosis and cryptococcal meningitis (Bennett, 1977). Its selectivity depends on the fact that mammals secrete it unchanged (just as they do cytosine), whereas fungi convert it to 5-fluorouracil and then elaborate this to its cytostatic nucleotide. 

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