flucytosine

Flucytosine is an antifungal small molecule used primarily to treat serious systemic infections caused by susceptible strains of Candida and Cryptococcus species. It is often administered in combination with amphotericin B for enhanced efficacy, particularly in the treatment of cryptococcal meningitis and other severe fungal infections. Flucytosine acts as an antimetabolite; it enters fungal cells via cytosine permease and is converted intracellularly into 5-fluorouracil (5-FU). The active metabolites disrupt both RNA and DNA synthesis by being incorporated into fungal RNA (as 5-fluorouridinetriphosphate) and inhibiting thymidylate synthase (via 5-fluorodeoxyuridinemonophosphate), leading to impaired protein synthesis and cell death. Resistance can develop rapidly if used as monotherapy.

Brand names

Ancobon

Other names

flucytosine5-fluorocytosine5-FC