Infantile spasm is a type of seizure seen in
an epilepsy syndrome during the infant and
early childhood years. This syndrome is
known as West Syndrome. An EEG is done
to confirm the diagnosis and will show a
chaotic brain wave pattern, hypsarrythmia.
The spasms can begin in the first year of
life, between 3 and 12 months of age.
Although, in most children, spasms stop by
age 2 – 3 years, about half of children will
begin to have other types of seizures. These
can occur before, or at the time the spasms
What are the spasms?
They are clusters (or groups) of brief
seizures that consist of a sudden bending
forward of the body either at the waist or
neck. This is followed by the legs being
stiff or the jerking forward of both the arms
and legs. These spasms are sometimes
called “jackknife seizures”. Some spasms
consist of arching of the body torso. Each
spasm can be brief (between 1 and 5
seconds) but can occur in clusters of 2 – 100
spasms at a time. It is common for the baby
to cry out after a spasm or be crabby
between spasms and when they stop.
Spasms occur more often when the child is
drowsy and falling asleep or upon waking
from sleep. They rarely occur during sleep.
Spasms may occur many times per day.
Sometimes spasms are confused with colic,
but the cramps of colic do not occur in
What causes the spasms?
It is a rare form of epilepsy that affects only
one baby out of three thousand. In about
20%of the cases, the cause is not known and
the baby develops in a normal way.
In the other cases, there are many reasons
that could cause this type of epilepsy:
ξ Brain malformations
ξ Brain injuries or infections
ξ Chromosome abnormalities
ξ Metabolic disorders
ξ Syndromes like tuberous sclerosis
that involve the brain, skin, and heart
What tests will be done?
An EEG or video EEG will be done
to confirm the diagnosis. EEG will
be done again some weeks later to
see if the treatment is helping.
MRI scan of the brain
Blood tests for metabolic disorders
What is the treatment?
The treatments for infantile spasms include
steroids by mouth, hormone shots (ACTH),
or medicines used to control other types of
ACTH is often used as the first treatment. It
is a hormone made by the pituitary gland. It
tells the adrenal glands to make and release
more cortisol, which acts much like a
steroid. It is more helpful than a steroid, but
it must be given as a shot, once daily for the
first few weeks, then slowly tapered until it
Steroids and ACTH have side effects but
can be safely managed:
High blood pressure
Increased risk of infection
Increased risk for bleeding in the
Puffiness from extra fluid. This can
make the face look fuller
High glucose level in the blood
Some children will need seizure medicine
such as Vigabatrin®, Depakote® or
Topamax® along with the steroids.
What is the prognosis?
The future course of the disorder and the
child’s development depend on the cause of
the seizures. Even with treatment of the
spasms, most children will have delays in
speech and motor skills. Many go on to
have other forms of epilepsy. When a child
has developed in a normal way before the
onset of the spasms, there is a better chance
stopping the seizures with medicine.
normal or mildly delayed speech and
motor skills and learning.
Many doctors feel that the quicker the
seizures are treated and controlled, the better
the results will be. Children who are not
treated often have frequent spasms for many
Some children may later have autism or a
syndrome called Lennox-Gastaut.
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