Flucytosine

INDICATIONS AND USAGE Flucytosine Capsules, USP are 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. Flucytosine Capsules, USP should be used in combination with amphotericin B for the treatment of systemic candidiasis and cryptococcosis because of the emergence of resistance to Flucytosine Capsules, USP (see MICROBIOLOGY ).

DOSAGE AND ADMINISTRATION The usual dosage of Flucytosine Capsules, USP 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 ). Flucytosine Capsules, USP should be used in combination with amphotericin B for the treatment of systemic candidiasis and cryptococcosis because of the emergence of resistance to Flucytosine Capsules, USP (see MICROBIOLOGY ).

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

ADVERSE REACTIONS The adverse reactions which have occurred during treatment with Flucytosine capsules 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. You may report side effects to FDA at 1-800-FDA-1088. You may also report side effects to Avet Pharmaceuticals Inc. at 1-866-901-DRUG (3784) or go to www.avetpharma.com.

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

DESCRIPTION Flucytosine Capsules USP, 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 lactose monohydrate, colloidal silicon dioxide, talc, sodium starch glycolate, magnesium stearate and hard gelatin capsule shell which contains gelatin, purified water, black iron oxide, FD&C Blue No.1, titanium dioxide and sodium lauryl sulfate for 250 mg strength; gelatin, purified water, black iron oxide and titanium dioxide for 500 mg strength. The imprinting ink contains black iron oxide, shellac, potassium hydroxide, titanium dioxide, povidone, sodium hydroxide and FD &C Red No. 40 aluminum lake for 250 mg and 500 mg strengths. Chemically, flucytosine is 5-fluorocytosine, a fluorinated pyrimidine which is related to fluorouracil and floxuridine. It is a white or almost white, crystalline powder with a molecular weight of 129.09 and the following structural formula: structural formula

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 Flucytosine Capsules USP 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.

HOW SUPPLIED Flucytosine Capsules USP, 250 mg are size 2 hard gelatin capsule with blue opaque cap and grey opaque body imprinted with "NL771" on the cap with black ink and "250" on the body with red ink filled with white to off white powder. Cartons of 30 capsules (6 capsules each blister pack x 5), NDC 0904-6834-07 Flucytosine Capsules USP, 500 mg are size 0 hard gelatin capsule with grey opaque cap and white opaque body imprinted "NL770" on the cap with black ink and "500" on the body with red ink, filled with white to off white powder. Cartons of 30 capsules (6 capsules each blister pack x 5), NDC 0904-6835-07 WARNING: These Unit Dose packages are not child resistant and are Intended for Institutional Use Only. Keep this and all drugs out of the reach of children. Store at 25°C (77°F); excursions permitted to 15°C - 30°C (59°F - 86°F). LUPIN and the are registered trademarks of Lupin Pharmaceuticals, Inc. Manufactured by: Novel Laboratories, Inc. Somerset, NJ 08873 Manufactured for: Lupin Pharmaceuticals, Inc. Naples, FL 34108 Packaged and Distributed by: MAJOR® PHARMACEUTICALS Indianapolis, IN 46268 USA Refer to package label for Distributor's NDC Number SAP code: 276392 Rev: 10/2024 logo