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Baloxavir marboxil Pregnancy and Breastfeeding Warnings

Baloxavir marboxil is also known as: Xofluza

Medically reviewed by Last updated on Nov 4, 2020.

Baloxavir marboxil Pregnancy Warnings

Animal studies have failed to reveal evidence of embryofetal toxicity at exposures about 5 and 7 times (rats and rabbits, respectively) the systemic drug exposure at the maximum recommended human dose; in rabbits administered 1000 mg/kg/day (a maternally toxic dose), fetal skeletal variations occurred and resulted in 2 abortions out of 19 pregnancies. There are no controlled data in human pregnancy.

Pregnant women have higher risk of severe complications from influenza, which may lead to adverse pregnancy and/or fetal outcomes.

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.

The manufacturer makes no recommendation regarding use during pregnancy.

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.

-Risks to mother and fetus associated with influenza during pregnancy should be considered.

See references

Baloxavir marboxil Breastfeeding Warnings

LactMed: An alternative agent may be preferred, especially while breastfeeding newborn or preterm infants.
-According to some authorities: Benefit should outweigh risk.

Excreted into human milk: Unknown
Excreted into animal milk: Yes (drug and its metabolites)

-No data available on the use of this drug during breastfeeding.
-Developmental and health benefits of breastfeeding should be considered as well as the mother's clinical need for this drug.
-The effects in the nursing infant are unknown; potential side effects in the breastfed child due to this drug or the mother's underlying condition should be considered.

Because this drug is 93% bound to plasma proteins, the amount in milk is likely to be low.

See references

References for pregnancy information

  1. "Product Information. Xofluza (baloxavir marboxil)." Genentech, South San Francisco, CA.

References for breastfeeding information

  1. "Product Information. Xofluza (baloxavir marboxil)." Genentech, South San Francisco, CA.
  2. National Library of Medicine (US) "Drugs and Lactation Database (LactMed) Available from: URL:" (2006):

Further information

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