Flucytosine

Flucytosine Uses, Dosage, Side Effects, Food Interaction and all others data.

A fluorinated cytosine analog that is used as an antifungal agent.

Flucytosine is an antimetabolite that acts as an antifungal agent with in vitro and in vivo activity against Candida and Cryptococcus. Flucytosine 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.

Flucytosine
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
Half Life
Volume of Distribution
Clearance
Interaction With other Medicine
Contradiction
Storage

Trade Name	Flucytosine
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
Weight	250mg, 500mg
Type	Oral capsule
Formula	C₄H₄FN₃O
Weight	Average: 129.0925 Monoisotopic: 129.03383997
Protein binding	28-31%
Groups	Approved, Investigational
Therapeutic Class
Manufacturer
Available Country	United States
Last Updated:	September 19, 2023 at 7:00 am

Uses

Flucytosine 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).

Flucytosine 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 Flucytosine 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. Flucytosine 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.

Flucytosine 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

Flucytosine 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

Flucytosine 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.