Neonatal abstinence syndrome (NAS) is a group of problems that occur in a newborn who was exposed to addictive opiate drugs while in the mother’s womb.
Neonatal abstinence syndrome may occur when a pregnant woman takes drugs such as heroin, codeine, oxycodone (Oxycontin), methadone or buprenorphine.
These and other substances pass through the placenta that connects the baby to its mother in the womb. The baby becomes dependent on the drug along with the mother.
If the mother continues to use the drugs within the week or so before delivery, the baby will be dependent on the drug at birth. Because the baby is no longer getting the drug after birth, withdrawal symptoms may occur as the drug is slowly cleared from the baby’s system.
Withdrawal symptoms also may occur in babies exposed to alcohol, benzodiazepines, barbiturates, and certain antidepressants (SSRIs) while in the womb .
Babies of mothers who use other addictive drugs (nicotine, amphetamines, cocaine, marijuana,) may have long-term problems. While there is no clear evidence of a neonatal abstinence syndrome for other drugs, they may contribute to the severity of a baby’s NAS symptoms.