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Infantile Spasms


M. Cristina Victorio

, MD, Akron Children's Hospital

Reviewed/Revised Mar 2023
Topic Resources

In infantile spasms, children suddenly raise and bend their arms, bend their neck and upper body forward, and straighten their legs.

  • The spasms are usually caused by serious brain disorders.

  • Many children who have infantile spasms also develop abnormally or have intellectual disability.

  • Electroencephalography is done to diagnose the disorder, and analysis of samples of blood, urine, and the fluid around the spinal cord as well as brain imaging help doctors identify the cause.

  • Adrenocorticotropic hormone, a corticosteroid, and vigabatrin are medications that help control the spasms.

Infantile spasms are a type of seizure Seizures in Children Seizures are a periodic disturbance of the brain’s electrical activity, resulting in some degree of temporary brain dysfunction. When older infants or young children have seizures, they often... read more . A seizure is an abnormal, unregulated electrical discharge that occurs within the brain and temporarily interrupts normal brain function.

Infantile spasms last for only a few seconds but typically occur close together in a series that lasts several minutes. Children may have many series of spasms a day. Spasms usually start when children are younger than 1 year of age. They may stop by 5 years of age, but often, another type of seizure then develops.

Causes of Infantile Spasms

Usually, infantile spasms occur in infants who have a serious brain disorder or developmental problem, which may have already been diagnosed. These disorders include

Sometimes no cause of infantile spasms can be identified.

Symptoms of Infantile Spasms

Spasms usually consist of a sudden jerk (spasm) of the trunk and limbs that looks very much like the infant has startled. Sometimes the spasms involve only slight nodding of the head.

Spasms may last several seconds, and children usually have many spasms in clusters, one right after the other.

Spasms typically occur soon after children wake up and occasionally occur when falling asleep.

When infantile spasms start, children who are developing normally may at least temporarily stop smiling or lose developmental skills that they have learned, such as being able to sit up or roll over.

Diagnosis of Infantile Spasms

  • Electroencephalography

  • Magnetic resonance imaging

  • Sometimes blood and urine tests and a spinal tap

Doctors diagnose infantile spasms based on symptoms and results of electroencephalography (EEG) Electroencephalography Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Imaging tests commonly used to diagnose nervous system (neurologic) disorders... read more Electroencephalography , which is done to check for specific patterns of abnormal electrical activity in the brain. EEG is done while children are sleeping and while they are awake.

Other tests are done to look for the cause:

If the cause of infantile spasms is still unclear, genetic tests may be done.

Treatment of Infantile Spasms

  • Adrenocorticotropic hormone

  • A corticosteroid

  • Vigabatrin

Because early control of infantile spasms is associated with a better developmental outcome, early identification and treatment of spasms are essential.

Children are prescribed one of the following three medications.

Adrenocorticotropic hormone (ACTH) can be injected into a muscle once a day. ACTH therapy is typically continued for 2 weeks and then tapered off over several weeks.

A corticosteroid (such as prednisone), given by mouth, may also be effective as an alternative to ACTH.

Vigabatrin is an antiseizure medication given by mouth. It is the medication of choice when tuberous sclerosis complex is the cause of the spasms. There is not enough evidence to support that any other antiseizure medication or a ketogenic diet is effective.

Sometimes epilepsy surgery Surgery In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before a seizure... read more is done to eliminate the cause of the spasms. An area of the brain may be surgically removed if seizures are caused by only that one area and that area can be removed without significantly affecting the child's ability to function.

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