Infantile spasms (a descriptor of epileptic spasms) are a form of epilepsy. They usually begin between 2-12 months of age and peak between 4-8 months of age. Infantile spasms impact more than 1,200 infants per year in the United States. While rare, these seizures can cause long-term injury to an infant's developing brain and if left untreated can cause problems with learning and development as well as seizures that are hard to control.

Infantile spasms can be mistaken for other conditions because the spasms can be very subtle in presentation. Therefore, prompt diagnosis and appropriate treatment may be delayed. This delay may have a direct negative impact on an infant's development.

What do Infantile Spasms look like?

Infantile spasms often occur in clusters right after a baby wakes up or falls asleep. Some signs of infantile spasms are:

  • Body stiffening
  • Back arching
  • Jerking at the tummy*
  • Arm raising*
  • Wide-eyed blinks or eye rolling*

*These movements are repetitive, subtle, and occur every 3-5 seconds lasting approximately 5-30 minutes in clusters.

What Causes Infantile Spasms?

There are many causes of infantile spasms; almost any brain abnormality or brain injury can be a trigger. Infantile spasms can be caused by structural changes in the brain due to a prior brain injury or a change in the way the brain has developed and genetic diseases.

How are Infantile Spasms Diagnosed?

To diagnose infantile spasms, a physician will complete a physical and neurological exam and perform a test called an electroencephalogram (EEG), which looks at electrical activity in the brain. If a baby has infantile spasms, the EEG usually shows a unique pattern called hypsarrhythmia when the seizures are not occurring. Other testing, including magnetic resonance imaging (MRI) and genetic testing, may also be needed for diagnosis.

Why is Early Diagnosis Important?

Infantile spasms are life threatening and require intervention in infancy. However, they are not usually diagnosed prenatally or upon exam in the nursery, and usually start later in infancy. Prompt diagnosis and treatment is crucial to optimize the infant’s development moving forward and prevent further loss of milestones, if possible.

How are Infantile Spasms Treated?

Pediatric neurologists may prescribe seizure medication as a first line treatment for infantile spasms. For infantile spasms that do not respond to medical treatment, there may be surgical options or dietary therapies. For more information on infantile spasms treatment, visit the Child Neurology Foundation Infantile Spasms webpage.

Knowing the Signs to ‘STOP’ Infantile Spasms

It is important for physicians to let families/caregivers know about what can be done to diagnose and treat infantile spasms. The below can be shared with families/caregivers.
Keep this easily remembered acronym in mind to 'STOP' Infantile Spasms:

  • See the signs: Clusters of sudden, repeated, uncontrolled movements like head bobs or body crunching.
  • Take a video: Record the symptoms and talk to your doctor immediately.
  • Obtain diagnosis: Confirm an abnormal brain wave pattern with an electroencephalogram (EEG) test.
  • Prioritize treatment: Treat spasms to minimize developmental delays.

Additional Resources

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American Academy of Pediatrics