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Voxelotor Pregnancy and Breastfeeding Warnings

Medically reviewed by Last updated on Dec 26, 2022.

Voxelotor is also known as: Oxbryta

Voxelotor Pregnancy Warnings

Benefit should outweigh risk

US FDA pregnancy category: Not assigned

Risk Summary: There are no data in human pregnancy to evaluate for drug-associated risks of major birth defects, miscarriage, or adverse maternal or fetal outcomes; animal studies have not shown evidence of adverse developmental outcomes.

-Women with sickle cell disease have an increased risk of adverse pregnancy outcomes; maternal risks include vaso-occlusive crises, preeclampsia, eclampsia, and maternal mortality; fetal risks include increased risk for intrauterine growth restriction, preterm delivery, low birth weight, and perinatal mortality.

In animal studies, no adverse developmental effects were observed in rats and rabbits at exposure of up to 2.8 and 0.3 times the maximum recommended human dose (MRHD) respectively. For rats receiving approximately 2.8 times MRHD, decreased maternal gestational body weight was observed and the offspring showed reduced survival and body weights throughout lactation, weaning, and maturation. All pregnancies have a background risk of birth defect, loss, or other adverse outcome. The estimated background risk of major birth defects and miscarriage for women with sickle cell disease is approximately 14% and up to 43%, respectively. There are no controlled data in human pregnancy.

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

Voxelotor Breastfeeding Warnings

Not Recommended

Excreted into human milk: Unknown
Excreted into animal milk: Yes

-Because of the potential for changes in the hematopoietic system in the breastfed infant, breastfeeding is not recommended during treatment and for at least 2 weeks after the last dose.

There are no data on the effects of this drug on the breastfed infant or its effects on milk production. This drug is present in the milk of lactating rats.

See references

References for pregnancy information

  1. "Product Information. Oxbryta (voxelotor)." Global Blood Therapeutics, Inc. (2019):

References for breastfeeding information

  1. United States National Library of Medicine "Toxnet. Toxicology Data Network." (2013):
  2. "Product Information. Oxbryta (voxelotor)." Global Blood Therapeutics, Inc. (2019):

Further information

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