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Nitisinone Pregnancy and Breastfeeding Warnings

Nitisinone is also known as: Nityr, Orfadin

Medically reviewed by Last updated on Sep 9, 2020.

Nitisinone Pregnancy Warnings

Pregnant mice dosed at 2 times the maximum clinical dose experienced increased gestation length. In mice and rabbits, embryotoxicity (decreased fetal weights, increased early intra-uterine deaths, and increased post-implantation loss) and fetal abnormalities (incomplete skeletal ossification in mice, umbilical hernia, gastroschisis, reduce or absent lung, increased skeletal malformations and variations in rabbits) were observed at doses from 5 mg/kg/day during organogenesis (less than maximum clinical dose based on body surface area). 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 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.

Use is not recommended unless the benefit outweighs the risk to the fetus

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

Risk Summary: Limited data in pregnant women are insufficient to determine a drug-associated risk of adverse developmental outcomes; animal studies have shown reproductive toxicity.

See references

Nitisinone Breastfeeding Warnings

Benefit should outweigh risk

Excreted into human milk: Unknown
Excreted into animal milk: Probably

-There are no data on the effects of this drug on the breastfed infant or its effects on milk production.
-The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for this drug and any potential adverse effects to the breastfed infant from the drug or from the underlying maternal condition.

Nursing rat pups exposed to this drug only by dams given 100 mg/kg/day orally, have shown reduced pup weight and the development of corneal opacities. This dose is estimated to be 9 times the maximum clinical dose based on body surface area.

See references

References for pregnancy information

  1. "Product Information. Orfadin (nitisinone)." Orphan Pharmaceuticals USA, Inc, Nashville, TN.
  2. "Product Information. Nityr (nitisinone)." Cycle Pharma, Boston, MA.
  3. Cerner Multum, Inc. "Australian Product Information." O 0

References for breastfeeding information

  1. "Product Information. Nityr (nitisinone)." Cycle Pharma, Boston, MA.
  2. Cerner Multum, Inc. "Australian Product Information." O 0
  3. "Product Information. Orfadin (nitisinone)." Orphan Pharmaceuticals USA, Inc, Nashville, TN.

Further information

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