Neonatal abstinence syndrome (NAS) is a condition that can happen when a baby is exposed to certain medicines or drugs before birth. Neonatal opioid withdrawal syndrome (NOWS) is a type of NAS that happens when a baby is exposed to opioids before birth. When opioids or other drugs are used during pregnancy, the baby can become used to them. Then after birth the baby may have withdrawal symptoms because the drug is no longer in their body.

Most drugs and medicines that are taken during pregnancy pass from the bloodstream to the baby. Some are more likely to cause NAS than others. They include:

• Opioid drugs such as heroin.
• Opioid medicines such as codeine and oxycodone.
• Medicines such as buprenorphine or methadone that are used to treat opioid use disorder.
• Products of a type of plant called kratom.
• Medicines to treat depression, such as fluoxetine, sertraline, or citalopram.
• Nicotine from tobacco use.

Alcohol use can also cause a different set of problems. These are called fetal alcohol spectrum disorders (FASDs).

Signs of withdrawal may start 24 to 48 hours after birth. Or they may start as late as 5 to 10 days after birth. The timing depends on the drug or medicine. The signs in a full-term baby may include:

• Trembling.
• Too much crying or high-pitched crying.
• Sleep problems.
• Tight muscle tone.
• Overactive reflexes.
• Seizures.
• Yawning, stuffy nose, and sneezing.
• Poor feeding or trouble sucking.
• Vomiting or diarrhea.
• Sweating.
• Fever or unstable temperature.
• Fast breathing.

A preterm baby may have signs that are less severe, and the baby may get better faster. This may be because their nervous system is less mature. Or it may be because they were exposed to less drugs than a full-term baby.

The doctor will ask about your medicine or substance use. The more information you can give will help your baby. Be as clear, accurate, and detailed as you can. The time that you took the last medicine or drug is also important.

The doctor may use a scoring system, such as the modified Finnegan Neonatal Abstinence Scoring Tool or Eat, Sleep, Console. This is to keep track of how severe your baby's withdrawal symptoms are. This scoring will help to plan treatment. The doctor may check your baby's meconium, urine, and umbilical cord tissue for the presence of drugs or other substances. Some birth centers routinely screen all babies.

Treatment will depend on how severe your baby's symptoms are, your baby's age, and their general health. Treatment decisions may be based on your baby’s withdrawal symptoms using the modified Finnegan scoring tool. Treatment decisions can also be based on your baby's ability to eat, sleep, and be consoled. This is called ESC.

You are an important part of your baby's recovery. A baby with withdrawal may be fussy and unhappy. They may be hard to comfort. Some ways to help comfort your baby may include:

• Wrapping your baby snugly in a light blanket (swaddling).
• Skin-to-skin holding.
• Gentle rocking.
• Using a pacifier.
• Being in a quiet room with low light.
• Gentle handling.

Your baby may need extra calories added to feedings because crying and fussing use more energy. Your baby's doctor may advise you to offer frequent, small feedings with higher-calorie formula or breast milk. This may help support growth and ease feeding problems. Talk with your doctor about your plans to breastfeed to make sure it is safe for you and your baby.

Your baby may need I.V. fluids if they are dehydrated or have severe vomiting or diarrhea. Some babies may need medicines to help ease their withdrawal symptoms and provide comfort. Medicines can also prevent severe problems such as seizures. If medicine is needed, your baby will likely be given a medicine that is in the same family of drugs as the one causing withdrawal. Once the signs of withdrawal are under control, the amount of the medicine is slowly decreased. This helps wean your baby off the drug.

Your baby's doctor will talk with you about which treatments might work best for your baby.

Other problems may include:

• Poor growth before birth.
• Being born too soon.
• Seizures.
• Birth defects.

Even without NAS, prenatal drug contact is linked to later developmental delay. Some drugs have been linked to specific problems. These include:

• Opioids. These can cause serious withdrawal in the baby. Some signs can last as long as 4 to 6 months. Seizures may also occur in babies born to those who use opioids.
• Amphetamines. These can lead to low birth weight and preterm birth.
• Cocaine. This can cause poor growth. It also makes problems such as placental abruption more likely.
• Marijuana. This may cause lower birth weight. It may also cause later problems with learning and behavior.
• Alcohol. This can have major effects on babies before and after birth. It can slow growth during pregnancy and after birth. It can also cause problems of the head and face, heart defects, learning problems, and mental problems.
• Cigarette smoking. This may cause low birth weight. It may also put babies at higher risk for preterm birth and stillbirth.

Your baby will need ongoing follow-ups with their doctor to monitor their development and identify any developmental delays.

Contact the doctor if your baby has:

• Signs that don't improve or that get worse.
• New signs.