5-Fluorocystosine
5-Fluorocystosine Uses, Dosage, Side Effects, Food Interaction and all others data.
A fluorinated cytosine analog that is used as an antifungal agent.
5-Fluorocystosine is an antimetabolite that acts as an antifungal agent with in vitro and in vivo activity against Candida and Cryptococcus. 5-Fluorocystosine enters the fungal cell via cytosine permease; thus, flucytosine is metabolized to 5-fluorouracil within fungal organisms. The 5-fluorouracil is extensively incorporated into fungal RNA and inhibits synthesis of both DNA and RNA. The result is unbalanced growth and death of the fungal organism. Antifungal synergism between Ancobon and polyene antibiotics, particularly amphotericin B, has been reported.
| Trade Name | 5-Fluorocystosine |
| Availability | Prescription only |
| Generic | Flucytosine |
| Flucytosine Other Names | 5-FC, 5-Fluorocystosine, 5-Fluorocytosine, flucytosina, Flucytosine, Flucytosinum |
| Related Drugs | fluconazole, Diflucan, itraconazole, amphotericin b, voriconazole, posaconazole, Sporanox, Vfend, Fungizone, Ancobon |
| Type | |
| Formula | C4H4FN3O |
| Weight | Average: 129.0925 Monoisotopic: 129.03383997 |
| Protein binding | 28-31% |
| Groups | Approved, Investigational |
| Therapeutic Class | |
| Manufacturer | |
| Available Country | |
| Last Updated: | September 19, 2023 at 7:00 am |
Uses
5-Fluorocystosine is an antifungal indicated only to treat severe infections throughout the body caused by susceptible strains of Candida or Cryptococcus.
For the treatment (in combination with amphotericin B) of serious infections caused by susceptible strains of Candida (septicemia, endocarditis and urinary system infections) and/or Cryptococcus (meningitis and pulmonary infections).
5-Fluorocystosine is also used to associated treatment for these conditions: Bloodstream Infections, Candidiasis, Candidiasis, Systemic, Cryptococcal infections, Fungal endocarditis, Infections, Fungal, Meningitis, Fungal, Urinary tract infection fungal, Disseminated Cryptococcosis
How 5-Fluorocystosine works
Although the exact mode of action is unknown, it has been proposed that flucytosine acts directly on fungal organisms by competitive inhibition of purine and pyrimidine uptake and indirectly by intracellular metabolism to 5-fluorouracil. 5-Fluorocystosine enters the fungal cell via cytosine permease; thus, flucytosine is metabolized to 5-fluorouracil within fungal organisms. The 5-fluorouracil is extensively incorporated into fungal RNA and inhibits synthesis of both DNA and RNA. The result is unbalanced growth and death of the fungal organism. It also appears to be an inhibitor of fungal thymidylate synthase.
Toxicity
Oral, rat: LD50 = >15 gm/kg.
Food Interaction
No interactions found.5-Fluorocystosine Drug Interaction
Moderate: zoledronic acid, zoledronic acidUnknown: ciprofloxacin, ciprofloxacin, sulfamethoxazole / trimethoprim, sulfamethoxazole / trimethoprim, meperidine, meperidine, heparin, heparin, vitamin a topical, vitamin a topical, bioflavonoids, bioflavonoids, sotalol, sotalol, pyridoxine, pyridoxine, cholecalciferol, cholecalciferol
5-Fluorocystosine Disease Interaction
Major: myelosuppression, renal dysfunctionModerate: hemodialysis, hypokalemia
Elimination Route
Rapidly and virtually completely absorbed following oral administration. Bioavailability 78% to 89%.
Half Life
2.4 to 4.8 hours.
Elimination Route
5-Fluorocystosine is excreted via the kidneys by means of glomerular filtration without significant tubular reabsorption. A small portion of the dose is excreted in the feces.
Innovators Monograph
You find simplified version here 5-Fluorocystosine
