Flucytosine

Flucytosine Capsules USP 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. …

• 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 )

• The efficacy and safety of Flucytosine Capsules USP 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. …

• 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 )

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.

Flucytosine Capsules USP must be given with extreme caution to patients with impaired renal function. Since Flucytosine Capsules USP is excreted primarily by the kidneys, renal impairment may lead to accumulation of the drug. Flucytosine Capsules USP 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. Flucytosine Capsules USP must be given with extreme caution to patients with bone marrow depression. …

The adverse reactions which have occurred during treatment with Flucytosine Capsules USP 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. …

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. …

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. …

Tómala en cuanto te acuerdes, salvo que falte poco para la siguiente. En ese caso, sáltate la olvidada. Nunca tomes dos dosis a la vez para compensar. Revisa tu prospecto, porque algunos medicamentos son distintos.