Infantile Spasms


Infantile spasms are a special form of epilepsy which occurs during infancy. The spasms usually begin when the baby is between three and eight months of age. In approximately 50 per cent of cases, the cause of infantile spasms is not known, in the other 50 per cent, there are many different conditions affecting the brain, such as birth injury, meningitis or head trauma, which can cause this type of epilepsy.

The Spasms

Symptoms can vary from child to child, however there is usually a sudden spasm or bending (Flexion) of the body either at the trunk or neck. A baby who is not yet sitting up may by lying quite comfortably and will suddenly draw the legs up at the hips, throw the arms out and lift the head. It is not uncommon for the baby to cry out after a spasm and be rather irritable. Children who can sit will bend at the waist and their head will fall between their legs. Spasms usually occur in clusters, each one is brief, lasting only a few seconds. Seizures may occur more often when the child is drowsy, either just going off to the sleep or just having woken.


This form of epilepsy is caused by a variety of conditions, each with different outlooks.


When a child’s development has been normal prior to onset of the spasms, there is a better chance of:


a) controlling the seizures with medication, and
b) developing and learning being normal or only mildly delayed.
However, when infantile spasms are associated with structural damage to the brain, it is difficult to completely control the seizures and intellectual disability is very likely to be present.


In most babies the spasms will cease between the ages of two of four. Approximately half the children will continue to have other kinds of seizures when the infantile spasms have stopped.

Courtesy of the Epilepsy Foundation of Victoria

Reviewed June 2021