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Flucytosine Pregnancy and Breastfeeding Warnings

Flucytosine is also known as: Ancobon

Medically reviewed by Drugs.com. Last updated on Mar 11, 2019.

Flucytosine Pregnancy Warnings

This drug should not be used in pregnant women, or those likely to become pregnant, unless the benefit outweighs the risk.
-According to some authorities: This drug should be used during pregnancy only if the benefit outweighs the risk to the fetus.

AU TGA pregnancy category: B3
US FDA pregnancy category: Not assigned.

Risk summary: No data available on use of this drug in pregnant women to inform a drug-related risk.

Comments (according to some authorities):
-Females of childbearing potential: Effective contraception is required during therapy and for 1 month after the last dose; local protocol should be consulted regarding contraception timing.
-Male patients or their female partners of childbearing potential: Effective contraception is required during therapy and for 3 months after the last dose; local protocol should be consulted regarding contraception timing.
-If this drug is used during pregnancy, the patient should be apprised of the potential harm to the fetus; careful prenatal and postnatal monitoring recommended. If this drug is used up to delivery, neonatal monitoring (hematologic and hepatic) is recommended.

Animal studies have revealed evidence of teratogenicity and embryotoxicity. Vertebral fusions were observed at doses of 40 mg/kg/day (298 mg/m2/day or 0.051 times the human dose) in rats, while cleft lip and palate and micrognathia were seen at 700 mg/kg/day (5208 mg/m2/day or 0.89 times the human dose); a low incidence of cleft palate observed at 400 mg/kg/day (1380 mg/m2/day or 0.236 times the human dose) in mice was not considered statistically significant. No teratogenicity was observed in rabbits at doses up to 100 mg/kg/day (1423 mg/m2/day or 0.243 times the human dose). This drug crosses the placenta in humans. There are no controlled data in human pregnancy.

According to some authorities, this drug should not be used during pregnancy or in females of childbearing potential not using contraception unless clearly needed (e.g., in case of life-threatening infections) and there are no effective alternatives.

AU TGA pregnancy category B3: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans.

US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

See references

Flucytosine Breastfeeding Warnings

A decision should be made to discontinue breastfeeding or discontinue the drug, taking into account the importance of the drug to the mother.
-According to some authorities: Use is contraindicated.
-According to some authorities: Use is not recommended unless the benefit outweighs the risk.

Excreted into human milk: Unknown
Excreted into animal milk: Data not available

Comments:
-The effects in the nursing infant are unknown.

See references

References for pregnancy information

  1. "Product Information. Ancobon (flucytosine)." Roche Laboratories, Nutley, NJ.
  2. Cerner Multum, Inc. "Australian Product Information." O 0
  3. Melbourne: Therapeutic Guidelines Limited "eTG complete [Online] Available from: URL: http://online.tg.org.au/complete/desktop/tgc.htm." ([2014, Nov -]):
  4. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  5. Thompson GR 3rd, Cadena J, Patterson TF "Overview of antifungal agents." Clin Chest Med 30 (2009): 203-15, v

References for breastfeeding information

  1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  2. Cerner Multum, Inc. "Australian Product Information." O 0
  3. "Product Information. Ancobon (flucytosine)." Roche Laboratories, Nutley, NJ.
  4. Melbourne: Therapeutic Guidelines Limited "eTG complete [Online] Available from: URL: http://online.tg.org.au/complete/desktop/tgc.htm." ([2014, Nov -]):

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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