• People have epilepsy when they've had two or more unprovoked seizures.

• The Centers for Disease Control and Prevention estimates that 2.3 million Americans have epilepsy. The National Epilepsy Foundation puts the number closer to 3 million.

• 1 in 10 people will have a seizure in their lifetime and 1 in 26 will develop epilepsy, according to the National Epilepsy Foundation.

• In nearly 70 percent of the cases, the cause is unknown.

• Famous people with epilepsy include Supreme Court Justice John Roberts, rock musician Neil Young, former Major League Baseball manager Buddy Bell and nine-time NFL Pro Bowler Alan Faneca.

• 70 percent of epilepsy patients can expect to enter remission (that is, becoming seizure-free for at least five years) with proper medication, according to the National Epilepsy Foundation.