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Natalizumab Pregnancy and Breastfeeding Warnings

Natalizumab is also known as: Tysabri

Medically reviewed on October 16, 2017.

Natalizumab Pregnancy Warnings

Studies in animals have shown reduced pup survival and adverse hematologic effects on the fetus in doses higher than comparable human doses. Animal studies have not shown teratogenicity. There are no controlled data in human pregnancy.

AU TGA pregnancy category C: Drugs which, owing to their pharmacological effects, have caused or may be suspected of causing, harmful effects on the human fetus or neonate without causing malformations. These effects may be reversible. Accompanying texts should be consulted for further details.

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.

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

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

Risk Summary: In animal studies, administration during pregnancy caused fetal immunologic and hematologic effects at doses similar to the human dose and reduced offspring survival at doses greater than the human dose.

Comments:
-If a woman becomes pregnant while taking this drug, discontinuation of therapy should be considered.

See references

Natalizumab 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.

Excreted into human milk: Yes

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

This drug is excreted into breastmilk in some, but not all, women. The time of peak level in breastmilk is variable, but might be as long as 6 months. Because it is a large protein molecule, absorption is unlikely because it is probably destroyed in the infant GI tract. Some experts recommend avoiding breastfeeding with this drug, while others do not.

See references

References for pregnancy information

  1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  2. "Product Information. Tysabri (natalizumab)." Elan Pharmaceutical/Athena Neurosciences Inc, South San Francisco, CA.
  3. Pharmaceutical Society of Australia "APPGuide online. Australian prescription products guide online. Available from: URL: http://www.appco.com.au/appguide/default.asp." ([2006]):

References for breastfeeding information

  1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  2. "Product Information. Tysabri (natalizumab)." Elan Pharmaceutical/Athena Neurosciences Inc, South San Francisco, CA.
  3. Pharmaceutical Society of Australia "APPGuide online. Australian prescription products guide online. Available from: URL: http://www.appco.com.au/appguide/default.asp." ([2006]):
  4. United States National Library of Medicine "Toxnet. Toxicology Data Network. Available from: URL: http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT." ([cited 2013 -]):

Further information

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

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