Here’s how that can happen.

By Maggie O'Neill
Updated: July 10, 2019

Cameron Boyce, who starred in the Disney Channel’s television show Jessie, passed away at age 20 after having a seizure in his sleep, People reports.

His untimely death startled actors who worked with him, including Adam Sandler, who tweeted in response to his death, “Thank you, Cameron, for all you gave to us. So much more was on the way. All our hearts are broken.”

Boyce’s family said in a statement obtained by People: “It is with a profoundly heavy heart that we report that this morning we lost Cameron.” People reports that Boyce suffered from epilepsy.

What is epilepsy?

Epilepsy is a neurologic condition that can cause recurring seizures. About 50 million people worldwide have the disorder, according to the World Health Organization (WHO). In the US, about 470,000 children have it, the CDC says. The CDC also reports that new epilepsy diagnoses are most common in older adults and children. Some kids outgrow epilepsy after having the condition for a few years; however, other children diagnosed with epilepsy require life-long treatment, the Epilepsy Foundation says.

Three main types of seizures are categorized by different symptoms. Someone having a complex partial seizure might appear confused; these seizures could make a person unable to verbally respond to questions. Petit mal or absence seizures cause someone to stare into space or blink rapidly. And then there’s what most people think of when they hear seizure—the grand mal or tonic-clonic seizure. Symptoms include jerking arms or legs, loss of consciousness, and body stiffening.

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Epilepsy isn’t the only cause of seizures. Alcohol withdrawal, low blood sugar, high fever, and concussion can also result in a seizure.

The WHO says 70% of epileptic patients can control their seizures with antiseizure medication. But a small percentage of people with epilepsy die from sudden unexpected death in epilepsy (SUDEP). “The numbers vary from one in 1,000 to one in 2,000,” Steven Wolf, MD, director of pediatric epilepsy for the Mount Sinai Health System in New York City, tells Health. “The risk of SUDEP is like standing in the lobby of my building and a taxi crashing through the waiting area and running over you,” Dr. Wolf adds.

He explains that epileptic patients who die from SUDEP are usually found dead in their beds. However, seizures aren’t always to blame. “It can be a seizure or [something else] unexplained,” Dr. Wolf says. “We recently had a case with a young patient who clearly didn’t have a seizure. She had a best friend sleeping right in the bed with her and was found dead in bed. [Sometimes] the brain just stops breathing.”

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What should you do if you witness a seizure?

If someone around you suffers a tonic-clonic seizure, you should put something flat and soft under them and position them on their side, the CDC says, noting that this will help them breathe. (A common myth is that a person might swallow their tongue during a seizure, but this is false.)

The CDC also says that seizures don’t usually necessitate a 911 call. However, if a friend or family member who has never struggled with seizures has one, you should seek emergency medical care. If a seizure causes someone to stop breathing or it causes an injury, you should seek medical help then too. Seizures that occur in the water or that last longer than five minutes also require immediate medical attention.

RELATED: 6 Things That Can Trigger a Seizure Even If You Don’t Have Epilepsy

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