Regarding oral naltrexone use in pregnancy, which statement is correct?

• A. It Crosses The Placenta And Is Present In Breast Milk
• B. It Is Safe With No Data Needed
• C. It Does Not Cross The Placenta Or Enter Breast Milk
• D. It Is Contraindicated In All Trimesters

Answer: (A)

Naltrexone’s behavior in pregnancy hinges on how it moves through the body and into fetal and neonatal compartments. It’s a small, lipophilic molecule, so it readily crosses the placenta and can reach the fetus. It’s also excreted into breast milk, so nursing infants can be exposed as well. Because safety data in pregnancy and lactation are limited, we can’t claim it’s definitively safe, but the pharmacokinetic reality is that exposure to the fetus and to breastfed infants does occur. That makes the statement about placental transfer and presence in breast milk the correct one. The other options conflict with what we know about its ability to move into fetal and breast milk compartments and with the reality that safety data are not complete, nor is there universal contraindication across all trimesters.