Epilepsy isn’t something you can confirm on your own. It requires medical testing. But there are specific signs, patterns, and experiences that strongly suggest you should be evaluated for it. Around 0.7% of the global population, roughly 52 million people, live with active epilepsy, making it one of the most common neurological conditions. If you’ve had an unexplained episode of lost awareness, unusual movements, or strange sensations, here’s what to look for and what the diagnostic process involves.
What Counts as a Seizure
Most people picture a seizure as falling to the ground and shaking. That’s one type, but seizures come in many forms, and some are easy to miss entirely. A seizure is a burst of abnormal electrical activity in the brain. What it looks and feels like depends on where in the brain it starts and how far it spreads.
Focal seizures start on one side of the brain. In the milder form, you stay fully aware but experience odd sensations: a rising feeling in your stomach, a sudden wave of déjà vu, tingling, dizziness, or seeing flashing lights. In the more intense form, your awareness drops. You might stare blankly, smack your lips, pick at your clothes, or be unable to respond to people around you for a few minutes.
Generalized seizures involve both sides of the brain from the start. Tonic-clonic seizures (formerly called grand mal) cause muscle stiffness followed by rhythmic jerking, usually lasting a few minutes. You lose consciousness and may cry out, fall, or lose bladder control. Absence seizures are the opposite extreme: brief lapses in consciousness where you stare into space, blink rapidly, or make small chewing motions. These are especially common in children and can happen dozens of times a day without anyone noticing.
Warning Signs That Happen Before a Seizure
Some people with focal seizures experience an “aura” in the moments before a seizure begins. An aura is actually a small seizure itself, a brief burst of activity in one part of the brain that may or may not progress into something bigger. Common auras include a strange feeling in the stomach, sudden fear or anxiety, a strong sense of déjà vu, tingling in part of the body, dizziness, or seeing flashing lights. If you repeatedly experience these sensations before losing awareness or having involuntary movements, that pattern is significant and worth documenting.
What Happens After a Seizure
The recovery period after a seizure, called the postictal state, is itself a clue. On average it lasts five to 30 minutes, though it can stretch to a few days in some cases. Common symptoms include confusion, exhaustion, headache, muscle soreness, memory gaps, difficulty speaking, and mood changes like anxiety or agitation. If you’ve “come to” feeling deeply confused and physically drained with no memory of the past few minutes, and others describe unusual behavior or movements you don’t remember, that recovery pattern is characteristic of a seizure.
Seizure vs. Fainting
Fainting (syncope) and seizures can look similar to bystanders, and telling them apart matters. Some key differences:
- Duration: Fainting episodes typically last less than one minute. Seizures usually last longer.
- Triggers: Fainting often has an obvious trigger like standing up quickly, heat, dehydration, or an emotional shock. Seizures can strike without warning.
- Before the event: Fainting is usually preceded by tunnel vision, nausea, cold sweats, pallor, or dizziness. Seizure auras feel different: stomach sensations, déjà vu, tingling, fear.
- During the event: Tongue biting, loss of bladder control, lip smacking, random eye movements, and sustained convulsions all point toward a seizure rather than a faint. Fainting may involve brief jerking movements, but they’re short-lived.
- After the event: Recovery from fainting is usually quick. Post-seizure confusion, exhaustion, and memory loss lasting minutes to hours suggest a seizure.
Not All Seizures Mean Epilepsy
A single seizure does not equal epilepsy. The formal diagnostic criteria require at least two unprovoked seizures occurring more than 24 hours apart, or one unprovoked seizure combined with a high enough risk (60% or greater) of having another within the next 10 years. That risk level is determined by your doctor based on brain imaging, electrical activity tests, and your medical history.
It’s also possible to have episodes that look and feel exactly like seizures but aren’t caused by abnormal brain activity. These are called functional seizures (sometimes referred to as psychogenic nonepileptic seizures). They’re real, not faked, but they have a different cause and don’t respond to anti-seizure medications. Clues that point toward functional seizures include full-body shaking episodes lasting longer than 10 minutes, eyes closed during the episode, out-of-sync limb movements, and retained awareness during convulsive movements. The definitive way to tell the difference is an EEG recorded during an episode: normal electrical activity during the event points to functional seizures rather than epilepsy.
How Epilepsy Is Diagnosed
There’s no single blood test for epilepsy. Diagnosis involves piecing together your history, witness accounts, and several types of testing.
An EEG (electroencephalogram) is the most important test. Electrodes placed on your scalp record your brain’s electrical patterns. Your doctor looks for characteristic abnormalities that indicate where seizures originate and what type they are. A standard EEG takes about 30 minutes, but if your seizures are infrequent or happen at night, your doctor may recommend extended video-EEG monitoring, sometimes lasting hours or days in a hospital setting. This captures both the brain activity and a video of your body during an episode, which is especially useful for seizures that are subtle or happen during sleep.
An MRI scan of the brain looks for structural causes: scar tissue, tumors, malformations, or other abnormalities that could be triggering seizures. A CT scan may be done in emergency situations for a faster look. In some cases, especially in children, doctors also investigate genetic or autoimmune causes.
A neurological exam tests your behavior, movements, reflexes, and mental function to help classify the type of epilepsy and identify any related neurological issues.
What to Track Before Your Appointment
The most useful thing you can do before seeing a neurologist is keep a detailed record of your episodes. Doctors rely heavily on descriptions of what happened before, during, and after each event, because they rarely get to witness one firsthand. Record when the episode happened, how long it lasted, what you were doing beforehand, any unusual sensations leading up to it (auras), what your body did during the event, and how you felt afterward. Note potential triggers like sleep deprivation, stress, alcohol, illness, or missed meals.
If someone was with you during the episode, their account is invaluable. Even better, ask someone to safely record video of the next episode on their phone. A short clip showing your movements, eye position, and responsiveness gives a neurologist more diagnostic information than most verbal descriptions can. Wearable devices that detect convulsive movements are also now available and can help track seizure frequency, particularly for tonic-clonic seizures.
When a Seizure Is an Emergency
Most seizures end on their own within a few minutes and don’t require emergency medical care. A seizure becomes a medical emergency, called status epilepticus, when the active shaking phase of a convulsive seizure lasts longer than five minutes, or when seizures occur back to back without the person regaining consciousness between them. For nonconvulsive seizures (where the person is unresponsive but not shaking), the threshold is 10 minutes. Status epilepticus can cause brain damage and requires immediate treatment.