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Pentazocine Pregnancy and Breastfeeding Warnings

Pentazocine is also known as: Talwin

Pentazocine Pregnancy Warnings

Benefit should outweigh risk

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

Risk Summary: Available data in pregnant women are insufficient to inform a drug-associated risk for major birth defects and miscarriage; based on animal data, a potential risk to the fetus cannot be ruled out.

-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.

Animal studies during the early gestational period have shown neural tube defects at 4.4 times the maximum daily dose. Prolonged use of opioids during pregnancy for either medical or nonmedical use may cause physical dependence in the neonate and neonatal opioid withdrawal syndrome shortly after birth. Opioids cross the placenta and may produce respiratory depression in neonates (naloxone should be available for reversal of opioid-induced respiratory depression). There are no controlled data in human pregnancy.

Chronic opioid use may cause reduced fertility in males and females; it is unknown whether these effects on fertility are reversible.

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.

See references

Pentazocine Breastfeeding Warnings

This drug has been detected in human milk; newborn infants appear to be particularly sensitive to the effects of even small doses. Once a mother's milk comes in, it is best to provide pain control with nonnarcotic analgesics. The developmental and health benefits of breastfeeding should be considered along with the mother's need for this drug and any potential adverse effects on the breastfed infant or underlying maternal condition. Withdrawal symptoms may occur in breastfed infants when maternal administration of an opioid analgesic is stopped or when breastfeeding is stopped.

Benefit should outweigh risk

Excreted into human milk: Yes

-Prompt medical assistance should be sought for breastfed infants showing signs of increased sleepiness, difficultly breastfeeding, or limpness.

See references

References for pregnancy information

  1. Product Information. Talwin NX (pentazocine). Sanofi Winthrop Pharmaceuticals. 2001.

References for breastfeeding information

  1. Product Information. Talwin NX (pentazocine). Sanofi Winthrop Pharmaceuticals. 2001.

Further information

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