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Infantile Spasms


The Manual's Editorial Staff

Last full review/revision May 2020| Content last modified May 2020
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What are infantile spasms?

"Infantile" refers to babies under 1 year old. A "spasm" is a sudden uncontrolled movement. Infantile spasms are a type of seizure. A seizure is caused by an abnormal burst of electrical activity in the brain.

  • Each spasm causes a jerky movement that lasts a few seconds

  • Infants may have many spasms in a row over several minutes and then not have any for a while

  • Spasms usually start when babies are younger than 1 year and may continue to about age 5

  • Many babies who have infantile spasms have a serious brain disorder

  • Doctors check the baby's brainwaves using an EEG to diagnose infantile spasms

  • Doctors give the baby daily hormone shots and pills, along with anti-seizure pills

What do infantile spasms look like?

Babies having an infantile spasm usually:

  • Jerk their whole body

  • Raise and bend their arms

  • Bend their neck and upper body forward

  • Straighten their legs

Each spasm lasts for several seconds. They usually occur in groups, one right after the other for several minutes. Infants typically have the spasms right after they wake up. Sometimes they have spasms while they're sleeping.

What causes infantile spasms?

Sometimes the cause isn't known. But usually infantile spasms occur in infants who have a serious brain disorder.

Babies with brain disorders that cause spasms usually develop slower than other babies. For example, they may take longer to stand, walk, or understand language. Later on they may have problems thinking and communicating.

How do doctors know if my baby is having infantile spasms?

Your baby's doctor may do a test called an EEG. This test measures brain waves. Doctors can recognize infantile spasms by the brain wave pattern seen on the EEG.

  • During this test, small sensors are placed with stickers on your baby's head

  • The test is painless

  • The EEG may be done while your baby is awake or asleep

Doctors may also do tests to look for the cause of the spasms. Such tests could be:

  • Blood and urine tests

  • MRI (scan showing detailed pictures) of your baby's brain

  • Genetic tests

What is the treatment for infantile spasms?

There's no cure for infantile spasms. Your baby's doctor will try to decrease the number and intensity of spasms by giving your baby medicines, such as:

  • Adrenocorticotropic hormone (ACTH) — a shot that your baby will get once a day

  • A corticosteroid to take by mouth

  • An anticonvulsant (anti-seizure) medicine to stop the spasms

If daily medicines don't help control your baby's spasms, doctors might suggest surgery. With surgery, doctors remove a small area of the brain that's causing your baby's spasms. While such surgery sounds scary, in fact the baby's brain recovers quickly.

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