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Infantile Spasms


What Are Infantile Spasms?

Infantile spasms (IS) is a seizure disorder in babies. The seizures (or spasms) make muscles in the arms and legs stiff and bend the baby's head forward. They look very much like a startle.

Babies also might have slowed development or loss of skills (like babbling, sitting, or crawling). Although the spasms usually go away by the time a child is 4 years old, many babies with IS will have other kinds of epilepsy later in life.

What Do Infantile Spasms Look Like?

Spasms start suddenly and last a second or two. They often come one after another in a cluster that lasts several minutes. They happen most often just after waking. They're often mistaken for colic, reflux, or hiccupping.

A baby having a spasm might have:

What Causes Infantile Spasms?

Infantile spasms (also called West syndrome) can be caused by brain malformations, infections, brain injury, or abnormal blood vessels in the brain. IS also can happen in babies with certain metabolic and genetic disorders. In rare cases, a baby's infantile spasms are caused by vitamin B6 deficiency.

Sometimes, the cause isn't known. However, more and more gene mutations are being linked to infantile spasms.

How Are Infantile Spasms Diagnosed?

Infantile spasms are diagnosed by a pediatric neurologist (a doctor who specializes in brain, spine and nervous system problems). Testing may include:

How Are Infantile Spasms Treated?

Infantile spasms usually are treated with seizure medicines or steroids. If medicines don't control the spasms, a special diet, such as the ketogenic diet, might help. Sometimes, doctors may recommend surgery.

How Can I Help My Child?

To help your child, follow the doctor's instructions to:

Date reviewed: September 2017


Note: All information on KidsHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

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