There can be many causes of seizures. They can be triggered by alcohol withdrawal, high fevers and head injuries, to name a few. But epilepsy seizures have no known cause. According to Alison M. Pack, M.D., a professor of neurology at Columbia University Irving Medical Center, an epilepsy diagnosis can be made after someone has two unprovoked seizures. Or, if after one seizure, brain magnetic resonance imaging (MRI) or electroencephalogram (EEG) testing shows there is a six in 10 or higher chance that you will have another seizure.