Yes, epilepsy is a seizure disorder. The two terms are used interchangeably in most medical contexts, though “epilepsy” is the more precise clinical name. The National Institute of Neurological Disorders and Stroke defines epilepsy as “sometimes referred to as a seizure disorder,” and the terms describe the same condition: a brain disorder characterized by recurring, unprovoked seizures. That said, there’s an important distinction between having epilepsy and having a seizure. Up to 10% of people worldwide will experience a single seizure at some point in their lives, but most of them do not have epilepsy.
How Epilepsy Differs From a Single Seizure
A seizure is a single event. Epilepsy is a pattern. The difference comes down to whether seizures keep happening without an obvious outside cause.
Many seizures are “provoked,” meaning something specific triggered them. Common triggers include low or very high blood sugar, high fever, alcohol withdrawal, sleep deprivation, certain medications, heat illness, and stress. These seizures happen because the brain is temporarily pushed past a threshold, not because of an underlying condition. Once the trigger is removed, the seizures stop. Provoked seizures are not epilepsy.
Epilepsy involves “unprovoked” seizures, ones that occur without an identifiable temporary cause. A person is generally diagnosed with epilepsy after having at least two unprovoked seizures more than 24 hours apart. In some cases, a diagnosis can follow even a single unprovoked seizure if testing shows the risk of another seizure over the next 10 years is 60% or higher. A person can also be diagnosed if their symptoms match a recognized epilepsy syndrome.
How Epilepsy Is Diagnosed
Because seizures can look similar regardless of their cause, diagnosing epilepsy involves more than just observing what happened. Doctors rely on two main tools to understand what’s going on inside the brain.
An electroencephalogram, or EEG, records the brain’s electrical activity through small metal discs placed on the scalp. People with epilepsy often show characteristic changes in their brainwave patterns even between seizures, when they feel completely normal. Recording these patterns helps confirm that the brain has an ongoing tendency to produce seizures and can reveal what type of epilepsy someone has.
An MRI creates a detailed image of the brain’s structure using magnets and radio waves. It can reveal physical abnormalities, such as scar tissue, tumors, or developmental differences, that may be causing seizures. Not everyone with epilepsy has a visible brain abnormality, but when one is found, it often guides treatment decisions.
Types of Seizures in Epilepsy
Seizures fall into two main categories based on where they start in the brain.
Focal seizures begin on one side of the brain. They can cause changes in awareness, unusual sensations, or abnormal movements, typically on one side of the body. Some focal seizures spread to both sides of the brain, which can lead to loss of consciousness and full-body movements. A person experiencing a focal seizure might stare blankly, feel a strange taste or smell, or make repetitive motions like lip-smacking or hand-rubbing without realizing it.
Generalized seizures begin on both sides of the brain at the same time. They usually cause loss of consciousness and may involve convulsions, muscle stiffening, or sudden jerking on both sides of the body. The tonic-clonic seizure (formerly called “grand mal”) is the type most people picture when they think of epilepsy, but generalized seizures can also be subtler, like brief staring spells lasting only a few seconds.
How Many People Have Epilepsy
Between 4 and 10 out of every 1,000 people have active epilepsy at any given time, according to the World Health Organization. That makes it one of the most common neurological conditions worldwide. It can develop at any age, though it most often begins in childhood or after age 60.
Treatment and Long-Term Outlook
Anti-seizure medications are the first line of treatment, and they work for about two out of three people with epilepsy. These medications don’t cure the condition, but they limit the spread of abnormal electrical activity in the brain, preventing seizures from occurring. Finding the right medication and dose can take time, and some people need to try more than one before achieving good control.
For the roughly one-third of people whose seizures don’t respond well to medication, other options exist, including surgery to remove the area of the brain where seizures originate, nerve stimulation devices, and specialized diets. The specific approach depends on the type and location of seizures.
The long-term outlook varies widely. Some forms of childhood epilepsy have high remission rates. In childhood absence epilepsy, for example, about 65% of patients eventually become seizure-free without needing daily medication. Others may need lifelong treatment. The type of epilepsy, how early treatment starts, and how well seizures respond to medication all influence the trajectory.
What to Do if Someone Has a Seizure
Knowing basic seizure first aid matters whether or not the person has epilepsy. Stay calm and stay with them. Move anything nearby that could cause injury. If the person is lying down, gently turn them on their side with their mouth pointing toward the ground to keep the airway clear. Put something soft under their head if possible, and loosen anything tight around their neck.
Time the seizure. If it lasts longer than five minutes, call 911. Also call for emergency help if the person has trouble breathing or waking up afterward, has a second seizure shortly after the first, is injured, is pregnant, has diabetes and loses consciousness, or has never had a seizure before.
Just as important is what not to do. Don’t hold the person down or try to restrain their movements. Don’t put anything in their mouth, as this can damage their teeth or jaw. Don’t offer food or water until they’re fully alert.