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Oxymorphone Pregnancy and Breastfeeding Warnings

Oxymorphone is also known as: Numorphan, Numorphan HCl, Opana, Opana ER

Medically reviewed on December 12, 2017

Oxymorphone Pregnancy Warnings

This drug should be used during pregnancy only if the benefit clearly outweighs the risk to the fetus.

US FDA pregnancy category: C

-Prolonged use of opioids during pregnancy can result in physical dependence in the neonate; women should be advised of the risk of neonatal abstinence syndrome and ensure that appropriate treatment will be available.
-Long-acting opioids should not be used during and immediately prior to labor, when short acting analgesics or other analgesic techniques are more appropriate.

Animal studies have shown that oxymorphone exposure during pregnancy is associated with reduced fetal weight. In a pre and postnatal developmental toxicity study, administration to female rats during gestation showed reduced litter size at a dose of 25 mg/kg/day (attributed to an increase in the incidence of still born pups) and an increase in neonatal death at 5 mg/kg/day or more (0.4 times a total human daily dose). Low pup birth weight, decreased post-natal weight gain, and reduced post-natal survival of pups occurred when born of dams treated with 25 mg/kg/day (about 2 times a total human dose). There are no adequate and well-controlled studies in pregnant women.

US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

See references

Oxymorphone Breastfeeding Warnings

Caution is advised; generally other agents are preferred over this drug during breastfeeding.

Excreted into human milk: Unknown
Excreted into animal milk: Data not available

Comments: Breastfed infants should be closely monitored for excess sedation and respiratory depression; withdrawal symptoms can occur when maternal administration of this drug is stopped.

See references

References for pregnancy information

  1. "Product Information. Opana ER (oxymorphone)." Endo Laboratories LLC, Chadds Ford, PA.
  2. "Product Information. Opana (oxymorphone)." Endo Laboratories LLC, Chadds Ford, PA.

References for breastfeeding information

  1. United States National Library of Medicine "Toxnet. Toxicology Data Network. Available from: URL:" ([cited 2013 -]):
  2. "Product Information. Opana ER (oxymorphone)." Endo Laboratories LLC, Chadds Ford, PA.
  3. "Product Information. Opana (oxymorphone)." Endo Laboratories LLC, Chadds Ford, PA.

Further information

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