Neonatal abstinence syndrome


Neonatal abstinence syndrome (NAS) is a group of problems that occur in a newborn who was exposed to addictive illegal or prescription drugs while in the mother’s womb. Babies of mothers who drink during pregnancy may have a similar condition.

Alternative Names


Causes, incidence, and risk factors

Neonatal abstinence syndrome occurs because a pregnant woman takes addictive illicit or prescription drugs such as:

  • Amphetamines
  • Barbiturates
  • Benzodiazepines (diazepam, clonazepam)
  • Cocaine
  • Marijuana
  • Opiates/Narcotics (heroin, methadone, codeine)

These and other substances pass through the placentato the babyduring pregnancy. The placenta isthe organ that connects the baby to its mother in the womb. The baby becomes addicted along with the mother.

At birth, the baby is still dependent on the drug. Because the baby is no longer getting the drug after birth, symptoms of withdrawal may occur.

Alcohol use during pregnancy can also cause problems in the baby. See: Fetal alcohol syndrome


The symptoms of neonatal abstinence syndrome depend on:

  • The type of drug the mother used
  • How the mother's body breaksdown the drug
  • How much of the drug she was taking
  • How long she used the drug
  • Whether the baby was born full-term or early (premature)

Symptoms depend on the drug involved. They can begin within 1 - 3 days after birth, or they may take 5 - 10 days to appear. They may include:

  • Blotchy skin coloring (mottling)
  • Diarrhea
  • Excessive crying or high-pitched crying
  • Excessive sucking
  • Fever
  • Hyperactive reflexes
  • Increased muscle tone
  • Irritability
  • Poor feeding
  • Rapid breathing
  • Seizures
  • Sleep problems
  • Slow weight gain
  • Stuffy nose, sneezing
  • Sweating
  • Trembling (tremors)
  • Vomiting

Signs and tests

It is important to have your baby checked out by a pediatrician. Many other conditions can produce the same symptoms as neonatal abstinence syndrome.

The doctor will ask questions about the mother's drug use, such as what drugs she took during pregnancy, and when she last took them.

Tests that may be done to diagnose withdrawal in a newborn include:

  • Neonatal abstinence syndrome scoring system, which assigns points based on each symptom and its severity. The infant’s score can help determine treatment.
  • Toxicology screen of first bowel movements (meconium)
  • Urine test (urinalysis)


Treatment depends on:

  • The drug involved
  • The infant’s overall health
  • Whether the baby was born full-term or premature

The health care team will watch the newborn carefully for signs of withdrawal, feeding problems, and weight gain. Babies who vomit or who are very dehydrated may need to get fluids through a vein (intravenously).

Infants with neonatal abstinence syndrome are often fussy and hard to calm. Tips to calm the infant down include:

  • Gently rocking the child
  • Reducing noise and lights
  • Swaddling the baby in a blanket

Some babies with severe symptoms need medicine to treat withdrawal symptoms. Medicines may include:

  • Morphine
  • Methadone

The doctor may prescribe the infant a drug similar to the one the mother used during pregnancy and slowly decrease the dose over time. This helps wean the baby off the drug and relieve some withdrawal symptoms. Breastfeeding may also be helpful.

Babies with this condition often have poor feeding or slow growth. Such babies may need:

  • A higher-calorie formula that provides greater nutrition
  • Smaller portions given more often

Support Groups

Expectations (prognosis)

Treatment helps relieve symptoms of withdrawal.


Drug and alcohol use during pregnancy can lead to many health problems in the baby, including:

  • Birth defects
  • Low birth weight
  • Premature birth
  • Small head circumference
  • Sudden infant death syndrome (SIDS)

Neonatal abstinence syndrome can last from 1 week to 6 months.

Calling your health care provider

Make sure your doctor or nurse know about all the drugs you take during pregnancy.

Call your doctor or nurse if your babyhas symptoms of neonatal abstinence syndrome.


Discuss all medications, alcohol and tobacco with your health care provider. If you are using drugs, including alcohol or tobacco, ask your health care provider for help with stopping as soon as possible. If you are already pregnant, talk to your health care provider about the best way to stop using and keep yourself and the baby safe.


Wong S, Ordean A, Kahan M; Maternal Fetal Medicine Committee; Family Physicians Advisory Committee; Medico-Legal Committee; Society of Obstetricians and Gynaecologists of Canada.Substance use in pregnancy. J Obstet Gynaecol Can. 2011 Apr;33(4):367-84.

Jansson LM, Velez M. Neonatal abstinence syndrome. Curr Opin Pediatr. 2012 Jan 5. [Epub ahead of print]

Bio LL, Siu A, Poon CY.Update on the pharmacologic management of neonatal abstinence syndrome.J Perinatol. 2011 Nov;31(11):692-701. .

McQueen KA, Murphy-Oikonen J, Gerlach K, Montelpare W.The impact of infant feeding method on neonatal abstinence scores of methadone-exposed infants.Adv Neonatal Care. 2011 Aug;11(4):282-90.

Cornelius MD, Day NL..Developmental consequences of prenatal tobacco exposure. Curr Opin Neurol. 2009 Apr;22(2):121-5.

Keegan J, Parva M, Finnegan M, Gerson A, Belden M.Addiction in pregnancy. JAddict Dis. 2010 Apr;29(2):175-91.