The medical condition defined by recurring seizures is called epilepsy. About 0.7% of the global population, roughly 52 million people, live with it. But having a single seizure doesn’t automatically mean you have epilepsy, and not all seizure-like episodes stem from the same cause. The terminology can get confusing, so here’s how doctors distinguish between the different conditions.
When Seizures Become Epilepsy
A seizure is an event. Epilepsy is the underlying condition. The International League Against Epilepsy defines epilepsy as a brain disease when any of these criteria are met: you’ve had at least two unprovoked seizures more than 24 hours apart, you’ve had one unprovoked seizure with a 60% or higher chance of having another within the next 10 years, or you’ve been diagnosed with a recognized epilepsy syndrome.
That distinction matters. Many people have a single seizure triggered by something temporary, like a high fever, alcohol withdrawal, or extremely low blood sugar, and never have another one. Those are called provoked seizures, and they don’t qualify as epilepsy on their own. Epilepsy specifically involves seizures that happen without an obvious external trigger, or that follow a recognized pattern doctors can identify as a syndrome.
Epilepsy can also be considered “resolved.” If you’ve been seizure-free for 10 years and off medication for at least 5, or you’ve aged out of a childhood epilepsy syndrome, the diagnosis no longer applies.
Types of Seizures
Seizures fall into a few broad categories based on where in the brain they start and what they look like.
Focal Seizures
Focal seizures begin in one specific area of the brain. When you stay fully conscious during the episode, it’s called a focal aware seizure (previously known as a simple partial seizure). These can cause a sense of déjà vu, a strange feeling in your stomach, or unusual movements, but you can often talk through them and remember them afterward.
When a focal seizure affects your awareness, it’s called a focal impaired awareness seizure (formerly a complex partial seizure). During these, you might look confused or dazed, pick at your clothes, smack your lips, or be unable to respond to questions for several minutes.
Generalized Seizures
Generalized seizures involve both sides of the brain from the start. The most recognized type is the tonic-clonic seizure, once called a “grand mal.” During the tonic phase, your muscles stiffen. During the clonic phase, they jerk rhythmically. These typically last a few minutes and leave you confused and exhausted afterward. You may cry out, lose consciousness, and fall.
On the other end of the spectrum are absence seizures, previously called “petit mal.” These cause brief lapses in consciousness, sometimes just a few seconds, where you stare blankly, blink rapidly, or make small chewing motions. They’re easy to miss entirely, especially in children.
Other generalized types include myoclonic seizures (quick, lightning-fast jerks), atonic seizures (sudden loss of muscle tone that can cause you to collapse), and tonic seizures (muscles go rigid without the jerking phase).
Seizures That Aren’t Epilepsy
Some episodes look and feel exactly like epileptic seizures but have a completely different cause. These are called functional seizures, also known as psychogenic nonepileptic seizures (PNES). They aren’t triggered by abnormal electrical activity in the brain. Instead, they’re a physical response from the nervous system to things like past trauma, environmental stress, injury, or pain.
Functional seizures can involve full-body shaking, loss of awareness, rapid head movements, and out-of-sync limb movements. The only reliable way to tell them apart from epileptic seizures is a video EEG, which records brain activity during an episode. If the brain’s electrical activity looks normal while the seizure is happening, the episode is functional rather than epileptic. This distinction is important because the two conditions require very different treatment approaches.
The Phases of a Seizure
Seizures aren’t just the visible event. They unfold in stages, and knowing the terminology helps you describe what’s happening to a doctor.
The prodrome is a warning period that can begin hours or even days before a seizure. Some people notice mood changes, irritability, or a general sense that something is off. Not everyone experiences this, but those who do often learn to recognize it over time.
The aura comes next and is considered the earliest part of the seizure itself. It might involve strange smells, visual disturbances, or a rising feeling in the stomach. Because the aura is technically seizure activity in a small part of the brain, it’s actually a focal aware seizure that sometimes spreads into a larger event.
The ictal phase is the main event, the period of active seizure activity in the brain. This is when the visible symptoms occur, whether that’s convulsions, staring, or loss of awareness.
The postictal phase is the recovery period afterward. Depending on the seizure type, this can involve confusion, fatigue, headache, muscle soreness, or difficulty speaking. It can last minutes to hours.
Reflex Epilepsy and Specific Triggers
Some people have seizures triggered by very specific stimuli, a condition called reflex epilepsy. The most common form is photosensitivity, where certain light frequencies, flickering screens, or sunlight glittering on water provoke seizures. But triggers can be surprisingly specific. Documented triggers include reading, writing, doing math, hearing certain music or sounds, tooth brushing, taking a hot bath, watching escalator steps move, and even thinking about particular topics. Some people are sensitive to repeated eye closure or specific colors.
When a Seizure Becomes an Emergency
Most seizures stop on their own within a few minutes. When one lasts longer than five minutes, or when seizures happen back-to-back without full recovery in between, it’s called status epilepticus. This is a life-threatening emergency. The longer a seizure continues, the less likely it is to stop without medical intervention, and prolonged seizure activity can cause brain damage. If you see someone seizing for more than five minutes, call emergency services immediately.