Sudden loss of consciousness can cause serious injury from falls and accidents. The turbulent electrical activity of a grand mal seizure can cause minor brain damage. However, most people who have epilepsy experience dozens or more seizures in their lives without suffering serious brain injury. Although individual seizures don't impair intelligence, recurring convulsive seizures may do so. Antiseizure drugs can completely prevent grand mal seizures in more than half the people with epilepsy and greatly reduce the frequency of seizures in another third.
Drugs are only slightly less effective for petit mal seizures.
Half of the people who respond to drug treatment can eventually discontinue the treatment without having a relapse. No single drug can control all types of seizures. Some people can have their seizures controlled with a single drug, while others have to take several. Because status epilepticus is an emergency, doctors must give the person large intravenous doses of an antiseizure drug as quickly as possible. Care is taken to prevent injuries during the prolonged seizure.