This article is from the Epilepsy FAQ, by Andrew Patrick (firstname.lastname@example.org) with numerous contributions by others.
There is no single cause of Epilepsy. Many factors can injure the nerve
cells in the brain or the way the nerve cells communicate with each
other. In approximately 65% of all cases there is NO known cause. The
following are some of the most frequently identified causes:
o Head injury that causes scaring of the brain tissue.
o Trauma at birth, or high fever.
o Excessively rough handling or shaking of infants.
o Certain drugs or toxic substances when administered in large
o Interruption of blood flow to the brain caused by stroke, tumour,
or certain cardiovascular problems.
o Diseases which alter the balance of blood or its chemical
structure, or diseases that damage the nerve cells in the brain.
When physicians can identify the underlying disorder, such as those
mentioned above, the condition is referred to as "Symptomatic"
Epilepsy. In some cases, however, the underlying disorder can't be
identified and this is called "Idiopathic" Epilepsy.