Neonatal Abstinence Syndrome

Also known as: NAS.

What is neonatal abstinence syndrome?

NAS is a group of problems that occur after delivery when a baby has been exposed during intrauterine life to illicit addictive drugs taken by his/her mother.

Examples include drugs like methadone, oxycodone, codeine, heroin, and cocaine (other drugs can also cause withdrawal and other symptoms/problems like alcohol-causing “fetal alcohol syndrome”, amphetamines, barbiturates and others).

Stopping medications, given to a baby after birth, suddenly (like morphine or fentanyl) may also give rise to withdrawal symptoms.

What causes neonatal abstinence syndrome?

Many drugs taken by a pregnant mother will cross the placenta and enter the baby. When addictive drugs do this, the baby’s exposure causes the baby to become addicted too. After birth, the baby’s dependence on the drug remains, so when the drug is suddenly not available, withdrawal symptoms result.

What are the symptoms of neonatal abstinence syndrome?

Symptoms vary widely depending on the specific drug, the amount used by the mother, whether the baby is born preterm or full term and the timing of the last dose taken before delivery. Symptoms can start soon after birth (24-48 hours) or be delayed for many days. Common symptoms include:

  • Trembling
  • Irritability with crying (high pitched)
  • Vomiting
  • Diarrhea
  • Sweating
  • Dehydration
  • Fever
  • Over reactive reflexes
  • Trouble sucking, feeding and/or sleeping
  • Seizures

In addition babies may be found to have poor intrauterine growth, prematurity and birth defects.

What are neonatal abstinence syndrome care options? 

Treatment will vary depending on the drug used and the severity of symptoms. Supportive care may include soothing by swaddling the baby, giving extra calories (for example given by a tube inserted into the stomach through the nose), intravenous fluids, plus treatments directed at the specific symptoms that occur.

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: November 18, 2021 04:00 PM

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