Does Dehydration Cause Seizures?

My son had am episode last night that started with a period of starring without being able to snap out of it for a while by his friends the followed by crazy behavior like hitting kicking bitting his phone all the time thinking he was going crazy. The episode slowly ended. His friends took him to the hospital and after tests all they could find that he was dehydrated. it sounded like some kind of seizure. He is 20 years old in college is an football player doesn t do drugs and doesn t see how anyone could have slipped him anything either. He says he felt like there was a demon in him. He remembers some not all that happened.