Cedars-Sinai Blog

What Is a Seizure?

seizure, brain, electrical activity, brain waves, Cedars-Sinai

A seizure is a symptom, just like a fever. It's not a disease. It happens when there's a disturbance in the brain's normal electrical activity.

An estimated 10% of people experience an unprovoked seizure during their lifetime. Epilepsy—when a person has multiple seizures during their lifetime or is at risk of having multiple seizures—is far less common, affecting only 1.2% of the population. 

"People who are suffering from Alzheimer's disease, Huntington's disease, stroke, or a traumatic brain injury are more likely to develop epilepsy."

Doctors generally identify seizures as focal (resulting from abnormal activity in one area of the brain), generalized (involving multiple areas of the brain), or unknown (because there's insufficient information about how they started). 

"Your symptoms depend on where the seizure is coming from," says neurologist Dr. Chrystal Reed. Seizures can take many forms, from confusion and staring off into space to uncontrolled jerking movements and loss of consciousness. 

While a seizure can last for a minute or more, chances are good you'll have no memory of the episode.

Seizure causes

"For many patients, doctors can't determine why a seizure happened," says Dr. Reed. "They can occur without warning, during sleep, or while the person is watching TV. Some episodes are so short that they go undetected."

A variety of factors can trigger a seizure, including:

Watching someone seize can be terrifying. If you're a bystander, try to coax them to lay flat on their side, away from potential harm, and don't put anything in their mouth.

Pay attention to the time. If the seizure lasts for more than 3 minutes, call 911.

Don't attempt to restrain them or hold them down, but instead wait for the episode to end. Then make sure a medical professional evaluates them. 

Treatment for seizures

Seizures can be deadly, depending on where and when they occur. If you're driving, for example, a 10- to 15-second lapse in consciousness can be dangerous.

That's why it's important to get a handle on the root cause—if one can be identified—and treat accordingly. 

"People who are suffering from Alzheimer's disease, Huntington's disease, stroke, or a traumatic brain injury are more likely to develop epilepsy," Dr. Reed says. "If we're able to determine that a patient is at high risk of having another seizure, we prescribe antiseizure medication." 

While antiseizure drugs can effectively control seizure activity, they also come with side effects, including mental exhaustion, depression, and irritability.

You can work with your healthcare provider to strike a balance between seizure control and medication side effects.

"In many cases, your doctor can even wean you off antiseizure medication after you've been seizure-free for 2 years," says Dr. Reed.

Left untreated, seizures can cause lasting damage to your brain, so working with epilepsy specialists to find the right treatment is key if you have repeated seizures. In cases where medication cannot control seizures, surgery may be an option.