The signs and symptoms of epilepsy vary depending on the part of the brain affected and the type of seizure (whether partial or generalized). Some seizures may barely be noticeable to the patient or witnesses.

Signs and symptoms of partial and generalized seizures may include:

People who witness an epileptic seizure should not attempt to move or disturb the person while the seizure is taking place. Instead, they should move any objects that may cause harm to the person. Nothing should be placed in the person's mouth (including fingers). Contrary to popular belief, it is physically impossible for a person to swallow their own tongue during a seizure. If this is the first time a person has had a seizure or if the seizure lasts five minutes or more, emergency services should be called.