API Fluorocytosine Drug 2022-85-7 for toxic antifungal Pyridines Pyrimidines

Quick detail

Flucytosine Introduction

Flucytosine, or 5-fluorocytosine, a fluorinated pyrimidine analogue, is a synthetic antimycotic drug.

It is structurally related to the cytostatic fluorouracil and to floxuridine. It is available in oral and in some countries also in injectable form. A common brand name is Ancobon. Flucytosine was first synthesized in 1957 but its antifungal properties were discovered in 1964. The drug is dispensed in capsules of 250 mg and 500 mg strength. The injectable form is diluted in 250 mL saline solution to contain 2.5 g total (10 mg/mL). The solution is physically incompatible with other drugs including amphotericin B.

It is on the World Health Organization's List of Essential Medicines, the most important medication needed in a basic health system.

Medical Application API Fluorocytosine:

1. Flucytosine by mouth is used for the treatment of serious infections caused by susceptible strains of Candida orCryptococcus neoformans. It can also be used for the treatment of chromomycosis (chromoblastomycosis), if susceptible strains cause the infection.

2. Flucytosine must not be used as a sole agent in life-threatening fungal infections due to relatively weak antifungal effects and fast development of resistance, but rather in combination with amphotericin B and/or azole antifungals such as fluconazole or itraconazole. Minor infections such as candidal cystitis may be treated with flucytosine alone. In some countries, treatment with slow intravenous infusions for no more than a week is also a therapeutic option, particular if the disease is life-threatening.

3. Serious fungal infections may occur in those who are immunocompromised. These people benefit from combination therapy including flucytosine, but the incidence of side-effects of a combination therapy, particular with amphotericin B, may be higher.