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ANCOBON Flucytosine 500 mg Capsule, 100-count — NDC 0187-3555-10 (Billing 00187-3555-10)

by Bausch Health US LLC · 100 CAPSULE in 1 BOTTLE

This is a package of 100 capsules of ANCOBON Flucytosine 500 mg Capsule from Bausch Health US LLC, marketed since Nov 1971 and currently FDA-listed. It is this product's only package size.

NDC 00187-3555-10
🏷️ FDA NDC (as labeled) 0187-3555-10 billing pads the labeler segment with a zero
Rx only Brand On market Non-controlled ⇄ Compare with another NDC
🗂️ FDA directory synced Oct 1, 2026 · this listing last changed Jul 24, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →

This page is curated, coded, and maintained by

Compiled from public FDA, CMS, DailyMed, NADAC, and related drug data sources. Editorial policy

Identity & classification

Regulatory identifiers FDA, NLM and CMS codes for this package

FDA NDC (as labeled) 0187-3555-10
Product NDC 0187-3555
11-digit billing NDC 00187355510
NCPDP billing unit EA — each (per item)
RxCUI 197702, 197703, 207125, 207127
UNII D83282DT06
UPC 0301873554103, 0301873555100
Application # NDA017001
SPL Set ID aea0df00-a88c-4a16-abcf-750f3ff2004e
Established class (EPC) Nucleoside Analog Antifungal
DEA schedule Non-controlled
Marketing category NDA
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 1971-11-26
Route ORAL
Dosage form CAPSULE
Substance FLUCYTOSINE
TE code (Orange Book) AB · RLD · RS

Drug-database identifiers Medi-Span GPI and First Databank GCN / HICL / AHFS classification

GPI-14 11000020000110
GPI class Ancobon
GCN Seq No 009543
GCN 42561
HICL code 004131
Ingredient (HICL) Flucytosine
HIC1 code W
Therapeutic class — broad (HIC1) Anti-Infecting Agents
HIC2 code W3
Therapeutic class — intermediate (HIC2) Antimycotics
HIC3 code W3B
Therapeutic class — specific (HIC3) Antifungal Agents
AHFS code 08:14.32.00
AHFS class Pyrimidine Antifungals
FDB label name ANCOBON 500 MG CAPSULE
FDB brand name Ancobon
Legend status F — Federal legend — prescription drug or device
Quick answers
  • GSN (GCN sequence number): 009543
  • GCN: 42561
  • GPI-14 (Medi-Span): 11000020000110
  • HICL (First Databank): 004131
  • AHFS class code: 08:14.32.00
  • RxCUI (RxNorm): 197702
Why two NDCs? The FDA registers this code as 0187-3555-10 — a 4-4-2 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the labeler segment → 00187-3555-10. Same drug, same package — only the format differs.
Where does this data come from?
Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

RxNorm drug class

This medicine belongs to the Nucleoside Analog Antifungal class.

Pharmacologic class Nucleoside Analog Antifungal
Drug family (ATC) Other antifungals for topical use, Other antimycotics for systemic use
Where does this data come from?
Therapeutic classes from RxNorm RxClass (U.S. National Library of Medicine) — Established Pharmacologic Class (FDA), ATC drug family (WHO) and mechanism of action, matched by this product’s RxCUI.

Clinical

Label name ANCOBON 500 MG CAPSULE Ingredient Flucytosine
📗 Our plain-language guide HelloPharmacist
  • That's a great question. Flucytosine can work alone against some fungi, but the problem is that the fungus can develop resistance to it pretty quickly when it's used by itself. Pai...
  • Why do I have to take flucytosine with another antifungal? Can't it work on its own?
  • Yes — and this is one of the most practical tips for taking this medication. Instead of swallowing all your capsules at once, try taking a few at a time over about 15 minutes. Spre...
  • The capsules are making me feel sick to my stomach. Is there anything I can do?
📖 Read our full Flucytosine guide →
Where does this data come from?
Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

Pricing

A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.

Price systemPer eachPer package
Retail pharmacies payNADAC · weekly Not in the retail survey — common for institutional, discontinued, or low-volume packs.
Medicaid paysCMS SDUD · 12 mo No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data.
Medicare drug plans payPart D · quarterly No Part D plan price is available for this NDC in our data.
ℹ️
No price is published for this exact package yet. CMS surveys NADAC per package size, so a different pack of the same drug often has one.
Where does this data come from?
NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

Packaging — all sizes for this product

Package NDCDescription Marketing startMarketing endStatus
00187-3555-10 You're viewing this Main listing 100 CAPSULE in 1 BOTTLE 1971-11-26 — Active

Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Ancobon 500 mgthis 00187-3555-10 Bausch 100 capsules — AB FDA listed —
Flucytosine 500 mg 00904-6835-07 Major 30 capsules — AB FDA listed —
Flucytosine 500 mg 23155-0861-01 Heritage 100 capsules — AB FDA listed —
Flucytosine 500 mg 40032-0770-01 Novel 100 capsules — AB FDA listed —
Flucytosine 500 mg 42385-0984-01 Laurus 100 capsules — AB FDA listed —
Flucytosine 500 mg 42794-0010-08 Sigmapharm 30 capsules — AB FDA listed —
Flucytosine 500 mg 43386-0770-01 Lupin 100 capsules — AB FDA listed —
Flucytosine 500 mg 50268-0332-12 AvPAK 20 capsules — AB FDA listed —
Flucytosine 500 mg 59651-0332-01 Aurobindo 100 capsules — — FDA listed —
Flucytosine 500 mg 60687-0610-21 American 30 capsules — AB FDA listed —
About this product: this is the brand-name version. Some generic versions are approved by the FDA, but we could not confirm current pharmacy availability from our pricing/market data.
Where does this data come from?
Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

Availability & generic status

🏛️
1971
On the market since
Nov 1971
📍
2026
Currently FDA-listed
55 years listed
🔒
·
Generic approved (availability unconfirmed)
see note
🔒Generic approved by FDA, but pharmacy availability is not confirmed

The FDA lists approved generic versions of this medicine, but that does not always mean a pharmacy can get one today. Patent rules, launch agreements, supply and pricing can affect when generics actually arrive.

Where does this data come from?
Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

Inactive Ingredients / Excipients

Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.

💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.

  • UNII XM0M87F357
    A dark iron oxide compound that gives medicines their black or dark color. It's used as a colorant in tablets and capsules to help identify the product and make it visually distinctive.
  • UNII 2G86QN327L
    Gelatin is a protein derived from animal collagen, commonly used in medicines as a gelling agent and capsule material. It helps create soft or hard capsule shells that hold and release medication, and can also thicken liquid formulations.
  • UNII J2B2A4N98G
    Lactose is a natural sugar derived from milk. In medications, it serves as a filler and binder to add bulk and help hold tablet or capsule ingredients together during manufacturing.
  • UNII O8232NY3SJ
    A plant-based carbohydrate derived from corn kernels. It acts as a filler to add bulk, a binder to hold ingredients together, and a disintegrant to help the tablet break apart in your stomach for absorption.
  • UNII 7SEV7J4R1U
    A powder made from a naturally occurring mineral. In medicines, talc works as a glidant and anti-caking agent, helping tablets and capsules flow smoothly during manufacturing and preventing clumping.
  • UNII 15FIX9V2JP
    Titanium dioxide is a bright white mineral powder commonly used as a colorant and opacifying agent. It makes pills and tablets white or lighter in color and helps make coatings non-transparent.

6 inactive ingredients listed in the exact product block matched to this NDC.

Where does this data come from?
Data sourced from official FDA Structured Product Labeling (SPL) via DailyMed — ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?
No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.
Why might an inactive ingredient be missing?
Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.
Can inactive ingredients matter?
Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

Manufacturer & labeler

LabelerBausch Health US LLC
Application holderBAUSCH HEALTH US LLC
FDA applicationNDA017001 (NDA)
Labeler code00187
First marketedNov 1971
Product typeHuman Prescription Drug
Portfolio41 products on file
The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).
Where does this data come from?
Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Very long sections are excerpted here and marked; the full text is on DailyMed (linked in the sources below). Jump with a chip, search within the label, or expand everything.
🚨 Boxed Warning 🎯 Indications and Usage ⏱️ Dosage and Administration ⛔ Contraindications ⚠️ Warnings 🤒 Adverse Reactions 🔄 Drug Interactions 🔄 Drug / Laboratory Test Interactions 🤰 Pregnancy 🧒 Pediatric Use 🆘 Overdosage 🧬 Clinical Pharmacology 📦 How Supplied / Storage and Handling 📋 Description ⚠️ Precautions 🍼 Nursing Mothers 🧬 Pharmacokinetics 📄 Carcinogenesis, Mutagenesis, Impairment of Fertility 📄 Package Label / Principal Display Panel
🚨 Boxed Warning 34 words ▾

WARNING Use with extreme caution in patients with impaired renal function. Close monitoring of hematologic, renal and hepatic status of all patients is essential. These instructions should be thoroughly reviewed before administration of ANCOBON.

🎯 Indications and Usage 97 words ▾

INDICATIONS AND USAGE ANCOBON is indicated only in the treatment of serious infections caused by susceptible strains of Candida and/or Cryptococcus . Candida: Septicemia, endocarditis and urinary system infections have been effectively treated with flucytosine. Limited trials in pulmonary infections justify the use of flucytosine.

Cryptococcus: Meningitis and pulmonary infections have been treated effectively. Studies in septicemias and urinary tract infections are limited, but good responses have been reported. ANCOBON should be used in combination with amphotericin B for the treatment of systemic candidiasis and cryptococcosis because of the emergence of resistance to ANCOBON (see MICROBIOLOGY ).

⏱️ Dosage and Administration 100 words ▾

DOSAGE AND ADMINISTRATION The usual dosage of ANCOBON is 50 to 150 mg/kg/day administered in divided doses at 6-hour intervals. Nausea or vomiting may be reduced or avoided if the capsules are given a few at a time over a 15-minute period. If the BUN or the serum creatinine is elevated, or if there are other signs of renal impairment, the initial dose should be at the lower level (see WARNINGS ).

ANCOBON should be used in combination with amphotericin B for the treatment of systemic candidiasis and cryptococcosis because of the emergence of resistance to ANCOBON (see MICROBIOLOGY ).

⛔ Contraindications 29 words ▾

CONTRAINDICATIONS ANCOBON is contraindicated in patients with a known hypersensitivity to the drug. ANCOBON is contraindicated in patients with known complete dihydropyrimidine dehydrogenase (DPD) enzyme deficiency (see WARNINGS ).

⚠️ Warnings 220 words ▾

WARNINGS ANCOBON must be given with extreme caution to patients with impaired renal function. Since ANCOBON is excreted primarily by the kidneys, renal impairment may lead to accumulation of the drug. ANCOBON serum concentrations should be monitored to determine the adequacy of renal excretion in such patients.

Dosage adjustments should be made in patients with renal insufficiency to prevent progressive accumulation of active drug. ANCOBON must be given with extreme caution to patients with bone marrow depression. Patients may be more prone to depression of bone marrow function if they: 1) have a hematologic disease, 2) are being treated with radiation or drugs which depress bone marrow, or 3) have a history of treatment with such drugs or radiation.

Bone marrow toxicity can be irreversible and may lead to death in immunosuppressed patients. Frequent monitoring of hepatic function and of the hematopoietic system is indicated during therapy. 5-Fluorouracil is a metabolite of flucytosine.

Dihydropyrimidine dehydrogenase is a key enzyme involved in the metabolism and elimination of 5-fluorouracil. Therefore, the risk of severe drug toxicity is increased when ANCOBON is used in individuals with deficiency in DPD. Possible drug toxicities include mucositis, diarrhea, neutropenia, and neurotoxicity.

Determination of DPD activity may be considered where drug toxicity is confirmed or suspected. In the event of suspected drug toxicity, consider stopping ANCOBON treatment.

🤒 Adverse Reactions 144 words ▾

ADVERSE REACTIONS The adverse reactions which have occurred during treatment with ANCOBON are grouped according to organ system affected. Cardiovascular: Cardiac arrest, myocardial toxicity, ventricular dysfunction. Respiratory: Respiratory arrest, chest pain, dyspnea.

Dermatologic: Rash, pruritus, urticaria, photosensitivity. Gastrointestinal: Nausea, emesis, abdominal pain, diarrhea, anorexia, dry mouth, duodenal ulcer, gastrointestinal hemorrhage, acute hepatic injury including hepatic necrosis with possible fatal outcome in debilitated patients, hepatic dysfunction, jaundice, ulcerative colitis, enterocolitis, bilirubin elevation, increased hepatic enzymes. Genitourinary: Azotemia, creatinine and BUN elevation, crystalluria, renal failure.

Hematologic: Anemia, agranulocytosis, aplastic anemia, eosinophilia, leukopenia, pancytopenia, thrombocytopenia, and fatal cases of bone marrow aplasia. Neurologic: Ataxia, hearing loss, headache, paresthesia, parkinsonism, peripheral neuropathy, pyrexia, vertigo, sedation, convulsions. Psychiatric: Confusion, hallucinations, psychosis.

Miscellaneous: Fatigue, hypoglycemia, hypokalemia, weakness, allergic reactions, Lyell’s syndrome. To report SUSPECTED ADVERSE REACTIONS, contact Bausch Health US, LLC at 1-800-321-4576 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

🔄 Drug Interactions 32 words ▾

Drug Interactions Cytosine arabinoside, a cytostatic agent, has been reported to inactivate the antifungal activity of ANCOBON by competitive inhibition. Drugs which impair glomerular filtration may prolong the biological half-life of flucytosine.

🔄 Drug / Laboratory Test Interactions 42 words ▾

Drug/Laboratory Test Interactions Measurement of serum creatinine levels should be determined by the Jaffé reaction, since ANCOBON does not interfere with the determination of creatinine values by this method. Most automated equipment for measurement of creatinine makes use of the Jaffé reaction.

🤰 Pregnancy 179 words ▾

Pregnancy Teratogenic Effects Flucytosine was shown to be teratogenic (vertebral fusions) in the rat at doses of 40 mg/kg/day (298 mg/M 2 /day or 0.051 times the human dose) administered on days 7 to 13 of gestation. At higher doses (700 mg/kg/day; 5208 mg/M 2 /day or 0.89 times the human dose administered on days 9 to 12 of gestation), cleft lip and palate and micrognathia were reported. Flucytosine was not teratogenic in rabbits up to a dose of 100 mg/kg/day (1423 mg/M 2 /day or 0.243 times the human dose) administered on days 6 to 18 of gestation.

In mice, 400 mg/kg/day of flucytosine (1380 mg/M 2 /day or 0.236 times the human dose) administered on days 7 to 13 of gestation was associated with a low incidence of cleft palate that was not statistically significant. Studies in pregnant rats have shown that flucytosine injected intraperitoneally crosses the placental barrier. There are no adequate and well-controlled studies in pregnant women.

ANCOBON should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

🧒 Pediatric Use 100 words ▾

Pediatric Use The efficacy and safety of ANCOBON have not been systematically studied in pediatric patients. A small number of neonates have been treated with 25 to 200 mg/kg/day of flucytosine, with and without the addition of amphotericin B, for systemic candidiasis. No unexpected adverse reactions were reported in these patients.

It should be noted, however, that hypokalemia and acidemia were reported in one patient who received flucytosine in combination with amphotericin B, and anemia was observed in a second patient who received flucytosine alone. Transient thrombocytopenia was noted in two additional patients, one of whom also received amphotericin B.

🆘 Overdosage 143 words ▾

OVERDOSAGE There is no experience with intentional overdosage. It is reasonable to expect that overdosage may produce pronounced manifestations of the known clinical adverse reactions. Prolonged serum concentrations in excess of 100 mcg/mL may be associated with an increased incidence of toxicity, especially gastrointestinal (diarrhea, nausea, vomiting), hematologic (leukopenia, thrombocytopenia) and hepatic (hepatitis).

In the management of overdosage, prompt gastric lavage or the use of an emetic is recommended. Adequate fluid intake should be maintained, by the intravenous route if necessary, since ANCOBON is excreted unchanged via the renal tract. The hematologic parameters should be monitored frequently; liver and kidney function should be carefully monitored.

Should any abnormalities appear in any of these parameters, appropriate therapeutic measures should be instituted. Since hemodialysis has been shown to rapidly reduce serum concentrations in anuric patients, this method may be considered in the management of overdosage.

🧬 Clinical Pharmacology ~3 min read ▾

CLINICAL PHARMACOLOGY Flucytosine is rapidly and virtually completely absorbed following oral administration. ANCOBON is not metabolized significantly when given orally to man. Bioavailability estimated by comparing the area under the curve of serum concentrations after oral and intravenous administration showed 78% to 89% absorption of the oral dose.

Peak serum concentrations of 30 to 40 mcg/mL were reached within 2 hours of administration of a 2 g oral dose to normal subjects. Other studies revealed mean serum concentrations of approximately 70 to 80 mcg/mL 1 to 2 hours after a dose in patients with normal renal function receiving a 6-week regimen of flucytosine (150 mg/kg/day given in divided doses every 6 hours) in combination with amphotericin B. The half-life in the majority of healthy subjects ranged between 2.4 and 4.8 hours.

Flucytosine is excreted via the kidneys by means of glomerular filtration without significant tubular reabsorption. More than 90% of the total radioactivity after oral administration was recovered in the urine as intact drug. Flucytosine is deaminated (probably by gut bacteria) to 5-fluorouracil.

The area under the curve (AUC) ratio of 5-fluorouracil to flucytosine is 4%. Approximately 1% of the dose is present in the urine as the α-fluoro-β-ureido-propionic acid metabolite. A small portion of the dose is excreted in the feces.

The half-life of flucytosine is prolonged in patients with renal insufficiency; the average half-life in nephrectomized or anuric patients was 85 hours (range: 29.9 to 250 hours). A linear correlation was found between the elimination rate constant of flucytosine and creatinine clearance. In vitro studies have shown that 2.9% to 4% of flucytosine is protein-bound over the range of therapeutic concentrations found in the blood.

Flucytosine readily penetrates the blood-brain barrier, achieving clinically significant concentrations in cerebrospinal fluid. Pharmacokinetics in Pediatric Patients Limited data are available regarding the pharmacokinetics of ANCOBON administered to neonatal patients being treated for systemic candidiasis. After five days of continuous therapy, median peak levels in infants were 19.6 mcg/mL, 27.7 mcg/mL, and 83.9 mcg/mL at doses of 25 mg/kg (N=3), 50 mg/kg (N=4), and 100 mg/kg (N=3), respectively.

Mean time to peak serum levels was of 2.5 ± 1.3 hours, similar to that observed in adult patients. A good deal of interindividual variability was noted, which did not correlate with gestational age. Some patients had serum levels > 100 mcg/mL, suggesting a need for drug level monitoring during therapy.

In another study, serum concentrations were determined during flucytosine therapy in two patients (total assays performed =10). Median serum flucytosine concentrations at steady state were calculated to be 57 ± 10 mcg/mL (doses of 50 to 125 mg/kg/day, normalized to 25 mg/kg per dose for comparison). In three infants receiving flucytosine 25 mg/kg/day (four divided doses), a median flucytosine half-life of 7.4 hours was observed, approximately double that seen in adult patients.

The concentration of flucytosine in the cerebrospinal fluid of one infant was 43 mcg/mL 3 hours after a 25 mg oral dose, and ranged from 20 to 67 mg/L in another neonate receiving oral doses of 120 to 150 mg/kg/day. MICROBIOLOGY Mechanism of Action Flucytosine is taken up by fungal organisms via the enzyme cytosine permease. Inside the fungal cell, flucytosine is rapidly converted to fluorouracil by the enzyme cytosine deaminase.

Fluorouracil exerts its antifungal activity through the subsequent conversion into several active metabolites, which inhibit protein synthesis by being falsely incorporated into fungal RNA or interfere with the biosynthesis of fungal DNA through the inhibition of the enzyme thymidylate synthetase. Activity In Vitro Flucytosine has been shown to be active against most strains of the following microorganisms both in vitro and in clinical infections. Candida alb… [Excerpted — this section continues on DailyMed.]

📦 How Supplied / Storage and Handling 115 words ▾

HOW SUPPLIED ANCOBON ® (flucytosine) Capsules are supplied as capsules containing 250 mg and 500 mg flucytosine as follows: NDC Strength Package Configuration Description 0187‑3554‑10 250 mg Bottles of 100 Gray and green capsules imprinted with “ANCOBON ® 250 ICN” 0187‑3555‑10 500 mg Bottles of 100 Gray and white capsules imprinted with “ANCOBON ® 500 ICN” Store at 25°C (77°F); excursions permitted to 15° to 30°C (59° to 86°F). Distributed by: Bausch Health US, LLC Bridgewater, NJ 08807 USA Manufactured by: Bausch Health Companies Inc.

Steinbach, MB R5G 1Z7, Canada ANCOBON is a trademark of Bausch Health Companies Inc. or its affiliates. © 2022 Bausch Health Companies Inc. or its affiliates Rev. 02/2022 9578603 20005061

📋 Description 107 words ▾

DESCRIPTION ANCOBON (flucytosine), an antifungal agent, is available as 250 mg and 500 mg capsules for oral administration. In addition to the active ingredient of flucytosine, each capsule contains corn starch, lactose and talc. The 250 mg capsule shell contains black iron oxide, D&C Yellow No.

10, FD&C Blue No. 1, FD&C Yellow No. 6, gelatin and titanium dioxide.

The 500 mg capsule shell contains black iron oxide, gelatin and titanium dioxide. Chemically, flucytosine is 5-fluorocytosine, a fluorinated pyrimidine which is related to fluorouracil and floxuridine. It is a white to off-white crystalline powder with a molecular weight of 129.09 and the following structural formula: Chemical Structure

⚠️ Precautions ~3 min read ▾

PRECAUTIONS General Before therapy with ANCOBON is instituted, electrolytes (because of hypokalemia) and the hematologic and renal status of the patient should be determined (see WARNINGS ). Close monitoring of the patient during therapy is essential. Laboratory Tests Since renal impairment can cause progressive accumulation of the drug, blood concentrations and kidney function should be monitored during therapy.

Hematologic status (leukocyte and thrombocyte count) and liver function (alkaline phosphatase, SGOT and SGPT) should be determined at frequent intervals during treatment as indicated. Drug Interactions Cytosine arabinoside, a cytostatic agent, has been reported to inactivate the antifungal activity of ANCOBON by competitive inhibition. Drugs which impair glomerular filtration may prolong the biological half-life of flucytosine.

Drug/Laboratory Test Interactions Measurement of serum creatinine levels should be determined by the Jaffé reaction, since ANCOBON does not interfere with the determination of creatinine values by this method. Most automated equipment for measurement of creatinine makes use of the Jaffé reaction. Carcinogenesis, Mutagenesis, Impairment of Fertility Flucytosine has not undergone adequate animal testing to evaluate carcinogenic potential.

The mutagenic potential of flucytosine was evaluated in Ames-type studies with five different mutants of S. typhimurium and no mutagenicity was detected in the presence or absence of activating enzymes. Flucytosine was nonmutagenic in three different repair assay systems (i.e., rec, uvr and pol). There have been no adequate trials in animals on the effects of flucytosine on fertility or reproductive performance.

The fertility and reproductive performance of the offspring (F1 generation) of mice treated with 100 mg/kg/day (345 mg/M 2 /day or 0.059 times the human dose), 200 mg/kg/day (690 mg/M 2 /day or 0.118 times the human dose) or 400 mg/kg/day (1380 mg/M 2 /day or 0.236 times the human dose) of flucytosine on days 7 to 13 of gestation was studied; the in utero treatment had no adverse effect on the fertility or reproductive performance of the offspring. Pregnancy Teratogenic Effects Flucytosine was shown to be teratogenic (vertebral fusions) in the rat at doses of 40 mg/kg/day (298 mg/M 2 /day or 0.051 times the human dose) administered on days 7 to 13 of gestation.

At higher doses (700 mg/kg/day; 5208 mg/M 2 /day or 0.89 times the human dose administered on days 9 to 12 of gestation), cleft lip and palate and micrognathia were reported. Flucytosine was not teratogenic in rabbits up to a dose of 100 mg/kg/day (1423 mg/M 2 /day or 0.243 times the human dose) administered on days 6 to 18 of gestation. In mice, 400 mg/kg/day of flucytosine (1380 mg/M 2 /day or 0.236 times the human dose) administered on days 7 to 13 of gestation was associated with a low incidence of cleft palate that was not statistically significant.

Studies in pregnant rats have shown that flucytosine injected intraperitoneally crosses the placental barrier. There are no adequate and well-controlled studies in pregnant women. ANCOBON should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Nursing Mothers It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from ANCOBON, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother. Pediatric Use The efficacy and safety of ANCOBON have not been systematically studied in pediatric patients.

A small number of neonates have been treated with 25 to 200 mg/kg/day of flucytosine, with and without the addition of amphotericin B, for systemic candidiasis. No unexpected adverse reactions were reported in these patients. It should be noted, however, that hypokalemia and acidemia were reported… [Excerpted — this section continues on DailyMed.]

🍼 Nursing Mothers 61 words ▾

Nursing Mothers It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from ANCOBON, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

🧬 Pharmacokinetics 218 words ▾

Pharmacokinetics in Pediatric Patients Limited data are available regarding the pharmacokinetics of ANCOBON administered to neonatal patients being treated for systemic candidiasis. After five days of continuous therapy, median peak levels in infants were 19.6 mcg/mL, 27.7 mcg/mL, and 83.9 mcg/mL at doses of 25 mg/kg (N=3), 50 mg/kg (N=4), and 100 mg/kg (N=3), respectively. Mean time to peak serum levels was of 2.5 ± 1.3 hours, similar to that observed in adult patients.

A good deal of interindividual variability was noted, which did not correlate with gestational age. Some patients had serum levels > 100 mcg/mL, suggesting a need for drug level monitoring during therapy. In another study, serum concentrations were determined during flucytosine therapy in two patients (total assays performed =10).

Median serum flucytosine concentrations at steady state were calculated to be 57 ± 10 mcg/mL (doses of 50 to 125 mg/kg/day, normalized to 25 mg/kg per dose for comparison). In three infants receiving flucytosine 25 mg/kg/day (four divided doses), a median flucytosine half-life of 7.4 hours was observed, approximately double that seen in adult patients. The concentration of flucytosine in the cerebrospinal fluid of one infant was 43 mcg/mL 3 hours after a 25 mg oral dose, and ranged from 20 to 67 mg/L in another neonate receiving oral doses of 120 to 150 mg/kg/day.

📄 Carcinogenesis, Mutagenesis, Impairment of Fertility 157 words ▾

Carcinogenesis, Mutagenesis, Impairment of Fertility Flucytosine has not undergone adequate animal testing to evaluate carcinogenic potential. The mutagenic potential of flucytosine was evaluated in Ames-type studies with five different mutants of S. typhimurium and no mutagenicity was detected in the presence or absence of activating enzymes. Flucytosine was nonmutagenic in three different repair assay systems (i.e., rec, uvr and pol).

There have been no adequate trials in animals on the effects of flucytosine on fertility or reproductive performance. The fertility and reproductive performance of the offspring (F1 generation) of mice treated with 100 mg/kg/day (345 mg/M 2 /day or 0.059 times the human dose), 200 mg/kg/day (690 mg/M 2 /day or 0.118 times the human dose) or 400 mg/kg/day (1380 mg/M 2 /day or 0.236 times the human dose) of flucytosine on days 7 to 13 of gestation was studied; the in utero treatment had no adverse effect on the fertility or reproductive performance of the offspring.

📄 Package Label / Principal Display Panel 64 words ▾

PRINCIPAL DISPLAY PANEL - 250 mg Capsule Bottle Label NDC 0187-3554-10 Rx only Ancobon ® (flucytosine) Capsules 250 mg 100 Capsules Each capsule contains 250 mg flucytosine BAUSCH Health 9578703 20005064 250mglabel

PRINCIPAL DISPLAY PANEL - 500 mg Capsule Bottle Label NDC 0187-3555-10 Rx only Ancobon ® (flucytosine) Capsules 500 mg 100 Capsules Each capsule contains 500 mg flucytosine BAUSCH Health 9578803 20005060 500mglabel

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗

Medicare Part D spend CMS · PART D · 2026 (Q1)

Medicare Part D (outpatient prescription) spending for Flucytosine (matched by generic name) — the program that covers self-administered drugs. 3 manufacturers.
⚠️ Drug-level data: CMS publishes Part D spending by drug, not by NDC — these figures combine every manufacturer, strength and package size sold under the name Flucytosine. That’s a different level of aggregation than the Medicaid card above, which is specific to this exact 11-digit NDC (pack size included), so the two aren’t directly comparable.
Period
Total Part D spend
$1.08M
Claims incl. refills
358
Beneficiaries
289
Spend / beneficiary
$3,734.54
Spend / claim
$3,014.76
Trend by period
💵 About the dollar figures: spending is what Part D plans paid before confidential manufacturer rebates, so the program’s real net cost is lower. A blank patient count means fewer than 11 people — CMS hides counts that small to protect privacy. Source: CMS Medicare Quarterly Part D Spending by Drug (data.cms.gov), updated quarterly.

Reported adverse events (FAERS)

Read carefully: FAERS reports are voluntary and unverified. Counts are not incidence, do not establish causation, are subject to reporting bias, and cannot be used to compare one drug to another. Shown for signal context only. Reports for Flucytosine — the ingredient across all brands.

Top reported reactions

Immune Reconstitution Inflammatory Syndrome103
Meningitis Cryptococcal92
Acute Kidney Injury87
Renal Impairment77
Condition Aggravated73
Cryptococcosis61
Disseminated Cryptococcosis61

Age at onset

Neonate2
Infant2
Child6
Adolescent2
Adult125
Elderly43

Reporter sex

1,369 reports
Male · 64%
Female · 36%
Unknown · 0%

Serious outcomes

Hospitalization628
Death486
Life-threatening158
Disabling14
Reports over time (by year) — tap or hover for the count & year
2019 2021 2023 2026 127 0
Most recent year is provisional (FAERS lags ~3 months).
Where does this data come from?
Adverse-event reports from the FDA Adverse Event Reporting System (FAERS) via openFDA. FAERS reports are voluntary and unverified — counts are not incidence and don’t establish causation.

About this NDC listing & data coverage

Finished prescription product
What data is (and isn’t) available for this NDC — tap to expand
NDC identity (package / product / labeler codes) ✓ Available
Labeler ✓ Available
Product & package description ✓ Available
Marketing category & status ✓ Available
Active ingredient / dosage form / route ✓ Available
FDA label (SPL via DailyMed) ✓ Available
Package photos — Not published for this NDC No photo available yet for this listing.
Inactive ingredients (structured) ✓ Available
NADAC pharmacy acquisition price (CMS) — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey.
Orange Book / therapeutic-equivalence data ✓ Available
HCPCS J-code billing crosswalk — Not published for this NDC Most self-administered / retail products have no J-code — that is normal.
Medicaid utilization (CMS SDUD) — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold.
“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?
The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.
Is the NDC printed on the package the same as the 11-digit billing NDC?
Yes, they identify this exact package in different formats. The form printed on the packaging and shown on DailyMed is the one the FDA registered. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero and the dashes are dropped. The Identity section at the top of this page lists each form of this code.
Is this package still being marketed?
Yes, per the latest FDA NDC Directory data on this page: this package is listed as actively marketed, with no marketing end date reported by Bausch Health US LLC. Listing status can change — the directory data on this page refreshes weekly.
Who lists this product with the FDA?
Bausch Health US LLC is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.
Do I need a prescription for this product?
This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.
This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.
Where does this data come from?
Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.
← 00187-3554-10 · Bausch 00187-4100-10 · Bausch →
For educational and professional reference only — not medical advice. Pricing reflects published NADAC and CMS ASP (free public data) and may differ from your acquisition cost; always verify before billing or dispensing.