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Zafirlukast Pregnancy and Breastfeeding Warnings

Brand names: Accolate

Medically reviewed by Drugs.com. Last updated on Jun 2, 2025.

Zafirlukast Pregnancy Warnings

This drug should be used during pregnancy only if clearly needed.

AU TGA pregnancy category: B1
US FDA pregnancy category: B

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

Animal studies have revealed evidence of maternal toxicity, deaths with increased incidence of early fetal resorption, and spontaneous abortions. There are no controlled data in human pregnancy.

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 B: Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.

See references

Zafirlukast Breastfeeding Warnings

Use should be avoided.

Excreted into human milk: Yes

Comments: The effects in the nursing infant are unknown.

Following repeated 40 mg twice-a-day dosing in healthy women, average steady-state concentrations in breast milk were 50 ng/mL compared to 255 ng/mL in plasma. Studies in mouse and rats showed a potential for tumorigenicity and enhanced sensitivity of neonatal rats and dogs to the adverse effects of this drug.

See references

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See also

References for pregnancy information

  1. (2001) "Product Information. Accolate (zafirlukast)." Astra-Zeneca Pharmaceuticals
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics."
  3. Cerner Multum, Inc. "Australian Product Information."

References for breastfeeding information

  1. (2001) "Product Information. Accolate (zafirlukast)." Astra-Zeneca Pharmaceuticals
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics."
  3. Cerner Multum, Inc. "Australian Product Information."

Further information

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

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