Caring For Babies With Neonatal Abstinence Syndrome (NAS)

5 Min Read Published April 17, 2017
Caring For Babies With Neonatal Abstinence Syndrome (NAS)

By Kathleen Colduvell RN, BSN, BA, CBC

Neonatal Abstinence Syndrome (NAS) occurs when a baby is exposed to drugs in the womb; consequently, the baby goes through withdrawal following birth. Babies can experience withdrawal due to the mother taking prescribed narcotics or by abusing street drugs. 

Prescription Medications and Neonatal Withdrawal

Almost every drug, prescription or non-prescription, passes from the mother's bloodstream through the placenta to the fetus. Illicit substances that cause dependence and addiction in the mother also cause addiction in the fetus. At birth, the baby's dependence on the substance continues, but since the drug is no longer available, the baby's central nervous system becomes overstimulated, causing symptoms of withdrawal. 

Prescription medications that can cause withdrawal include, but are not limited to: 

  • Narcotics (Vicodin, Percocet, and OxyContin)
  • Antidepressants (Prozac, Zoloft, and Celexa)
  • Benzodiazepines (Valium, Klonopin)

Some mothers take these medications prior to conception due to surgery or preexisting conditions. Unfortunately, some expectant mothers are unable to stop using these medications.  

It's important to ensure pregnant women are discussing all medications -- legal or illegal -- with their obstetrician or nurse-midwife. More information on medication safety during pregnancy can be found on the websites of the American Pregnancy Association and the American College of Obstetrics and Gynecology.

Street Drugs and the Fetus

Street drugs are very dangerous for fetuses. With prescription medications, there is a consistent level of medication in the mother and the fetus -- abusing street drugs doesn’t provide the same steady levels.  

According to the March of Dimes, approximately five percent of expectant mothers take street drugs during pregnancy; drugs taken may include cocaine, heroin, marijuana, Ecstasy, methamphetamines, and barbiturates.   

The use of street drugs can cause many problems, even prior to conception and delivery. Women can experience infertility, miscarriages, stillbirths, placental abruption (when the placenta peels away from the wall of the womb), preterm labor (labor that occurs prior to 37 weeks gestation), and even maternal death. 

The Negative Outcomes of Drug Abuse

The use of drugs during pregnancy can cause:

  • Withdrawal after delivery
  • Genetic birth defects
  • Heart defects
  • Infections
  • Microcephaly (small head circumference)
  • Low birth weight
  • Premature birth 
  • Learning and behavior problems
  • Slower than normal growth

The effects of specific drugs are as follows:


Fetuses eliminate cocaine much more slowly than adults, so the drug stays in the neonate’s body longer than the mother’s. Cocaine addiction has been linked to: 

  • Complete placental abruption, a medical emergency 
  • Poor fetal growth
  • Developmental delays
  • Learning disabilities
  • Lower IQ 


Heroin is extremely addictive to both mothers and unborn infants. It is extremely important that expectant mothers immediately discuss options with their medical provider. Heroin use has been linked to:

  • Increased risk of premature birth and low birth weight
  • Breathing difficulties
  • Hypoglycemia
  • Bleeding in the brain (intracranial hemorrhage)
  • Infant death 

Methamphetamine and amphetamine

The use of methamphetamine and amphetamine can lead to:  

  • Low birth weight and premature birth
  • Elevated heart rate in the unborn fetus
  • Decreased delivery of oxygen to the fetus from the placenta
  • Placental abruption
  • Fetal death


Marijuana use during pregnancy is currently extremely controversial. With the increasing number of states legalizing marijuana for either recreational and/or medicinal use, there has been an increase in the number of newborns hospitalized for associated complications. Marijuana has been associated with: 

  • Increased carbon monoxide and decreased oxygen crossing the placenta
  • Increased risk of miscarriage
  • Low birth weight and premature birth
  • Developmental delays
  • Behavioral and learning problems 

The Symptoms of Withdrawal

Withdrawal symptoms vary based on the type of medication or drug and the last time the substance was used.  

According to research, symptoms of NAS can begin as early as 24 to 48 hours after birth, or as late as five to 10 days after delivery. For example, heroin has a short half-life, and withdrawal occurs within 48–72 hours of birth, while methadone withdrawal on average occurs at 7–14 days. It's important to know that every withdrawal case is unique and symptoms may occur outside of this general timeframe.  

Below is a list of the most common symptoms experienced during withdrawal. These symptoms vary depending on the individual baby, and not every drug-addicted baby will experience every symptom.  

  • Tremors (trembling) 
  • Irritability (excessive crying) 
  • Myoclonic Jerks 
  • Restlessness (documented as 1-3 hours of sleep after feeding) 
  • High-pitched crying 
  • Hypertonia (increased muscle tone) 
  • Mottling 
  • Apnea 
  • Increased respiration (greater than 60 breaths per minute without retractions) 
  • Excessive sucking and/or rooting 
  • Hyperactive reflexes 
  • Seizures 
  • Yawning, stuffy nose, and sneezing 
  • Poor feeding and ineffective suck 
  • Vomiting 
  • Diarrhea 
  • Dehydration 
  • Sweating 
  • Fever or unstable temperature 

Assessing The Extent of Withdrawal 

Symptoms of withdrawal are important to document and make known to the medical provider. Hospitals use a neonatal abstinence scoring system to grade the severity of withdrawal. Common scoring symptoms include Finnegan, Ostrea, Lipsitz, Rivers, and the Neonatal Intensive Care Unit Network Neurobehavioral Scale (NNNS). 

Finnegan is the most widely used and accepted system. This scale examines 21 of the most common signs of neonatal withdrawal syndrome and is scored based on the severity of symptoms. The Finnegan scale is easy and reliable once proper training has occurred. Bias and subjectivity can affect scores. 


Treatment options vary depending on the institution and provider, the age of the newborn, and the extent of withdrawal. Babies suffering from withdrawal are often extremely irritable and have a difficult time being calmed. Swaddling, the use of motorized swings, and holding may provide comfort. 

These babies typically have a temporary increase in metabolic function, requiring higher calorie formula or IV fluids. If withdrawal is severe enough, medications such as morphine, phenobarbital, and/or methadone can be used to wean the newborn -- these medications should only be given under the direct supervision of an attending physician.  

NAS is a completely preventable problem. It requires complete honesty from the mother, which has been proven to be difficult to obtain. A mother should make every effort to stop using drugs prior to pregnancy or discuss other options with a medical provider in the interest of fetal health and survival. 

Next Up:  Heartbreaks and Triumphs from the NICU

Kathleen Colduvell RN, BSN, BA, CBC graduated with a degree in English and journalism before going back to nursing school. After graduating from Villanova University, she became a Neonatal Intensive Care Nurse. Currently, she works at one of the leading children’s hospitals in the country in the NICU, PICU, and CICU, as well as working as a Certified Breastfeeding Consultant.

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