Seizure is manifestation due to abnormal hyperysnchronization of brain electrical activity. A seizure may be or may not be epilepsy.
Seizure hasan immediate recognizable and treatable cause. It may be due to any kind of infection in brain, trauma to the brain or metabolic abnormalities like very low or very high glucose level, low sodium or calcium level in blood. To summarize seizure is manifestation of diseased or injured brain. If the underlying cause is treated seizure also gets resolved.
While epilepsy is the brain network problem characterized by tendency of brain to produce repeated seizures. In other words, repeated seizures without any immediate easily identifiable causeare called epilepsy. It doesn’t mean that cause of epilepsy is not known. Epilepsy has different cause which are not easily identifiable.
Common causes of epilepsy are abnormalities in brain structure or genetic. There is popular belief that genetic is always familial, it’s not like so. It may or may not be familial.