Epilepsy is a brain condition that causes repeated seizures

Epilepsy means your brain sometimes misfires electrically, causing seizures that happen more than once. A seizure is a sudden burst of electrical activity in the brain that changes how your body or mind works for a few seconds or minutes. The key word is "repeated"—if you have had one seizure, you do not have epilepsy. If you have had two or more seizures that were not caused by something temporary (like a high fever or low blood sugar), doctors may diagnose you with epilepsy.

During a seizure, the electrical misfiring can affect different parts of your brain, so seizures look different from person to person. Some people lose consciousness and their muscles shake. Others stay awake but cannot speak, or they stare blankly for a few seconds. Some people feel a warning sign—called an aura—before a seizure starts, like a strange smell or a tingling feeling. The seizure itself usually lasts from a few seconds to a couple of minutes.

Epilepsy is not contagious, and it is not a mental illness. It is a medical condition of the nervous system, like diabetes or asthma. Many people with epilepsy live full lives—they work, go to school, drive, and have families. The main difference is that they take medicine to prevent seizures or learn what triggers theirs and avoid those triggers.

Key Takeaways

  • Epilepsy is diagnosed when a person has had two or more seizures that were not caused by a temporary condition like fever or low blood sugar.
  • Seizures happen because of sudden electrical misfiring in the brain and can look very different depending on which part of the brain is affected.
  • A doctor will order an EEG (a test that records brain waves) and usually an MRI or CT scan to help confirm epilepsy and rule out other causes.
  • Most people with epilepsy can control their seizures with medicine, and some may eventually stop having seizures altogether.

How doctors tell the difference between one seizure and epilepsy

Having a single seizure does not mean you have epilepsy. A seizure can happen to anyone if the right (or wrong) conditions occur—a very high fever, a head injury, low blood sugar, or even extreme stress. These are called provoked seizures because something specific caused them. Once the fever breaks or the blood sugar rises, the seizures stop.

Epilepsy is diagnosed when seizures happen without an obvious cause, or when they keep happening even after the cause is treated. Doctors call these unprovoked seizures. If you have had two unprovoked seizures, or one unprovoked seizure plus a strong sign on a brain test that more will come, a neurologist (a doctor who specializes in the brain and nervous system) will usually diagnose epilepsy.

The reason doctors wait for a second seizure is that one seizure does not predict whether you will have another. Some people have one seizure in their lifetime and never have another. Others have a second one within days or weeks. By the time a second seizure happens, the pattern is clearer.

What tests doctors use to diagnose epilepsy

When you see a neurologist about seizures, they will ask detailed questions: What did you feel before the seizure? What did your body do? How long did it last? Did you remember it? They will also ask about your medical history, any head injuries, and whether seizures run in your family.

The main test is an EEG (electroencephalogram), which records the electrical activity of your brain. Small metal discs are pasted to your scalp, and wires connect them to a machine that prints out a graph of your brain waves. If you have epilepsy, the EEG often shows a distinctive pattern even when you are not having a seizure. Sometimes a neurologist will ask you to stay awake all night or hyperventilate during the test to try to trigger the pattern.

Your doctor will also order an MRI (magnetic resonance imaging) or CT scan (computed tomography), which take detailed pictures of your brain. These tests look for physical causes of seizures—a scar, a tumor, a malformed blood vessel, or an area where brain cells are arranged differently than normal. If the MRI or CT shows a specific problem, that helps explain why seizures are happening.

Blood tests may be ordered to rule out other causes, like very low blood sugar or an infection. In some cases, especially if seizures are hard to control, a neurologist might recommend more specialized tests like a 24-hour video EEG, where you stay in a hospital and are monitored continuously.

Different types of seizures and what they look like

Seizures are grouped into two main categories based on where in the brain they start. Focal seizures (also called partial seizures) begin in one area of the brain. Generalized seizures involve both sides of the brain from the start.

A focal seizure might cause your arm to shake, or you might feel a strange sensation in one part of your body. You might stay awake and aware, or you might lose consciousness. Some focal seizures cause you to stare blankly, smack your lips, or pick at your clothes without realizing it. These are called focal seizures with impaired awareness because you cannot respond normally to what is happening around you, even though you do not fall down.

Generalized seizures affect your whole body or your awareness right away. A tonic-clonic seizure (formerly called a grand mal seizure) is the most recognizable: your muscles suddenly tense, you lose consciousness, and your body shakes rhythmically. You might bite your tongue or lose bladder control. When it ends, you are usually confused and exhausted for minutes to hours afterward. An absence seizure (formerly called a petit mal seizure) is the opposite—you simply stare blankly for a few seconds, then snap back to normal with no memory of it. Atonic seizures cause a sudden loss of muscle tone, so you might drop to the ground. Myoclonic seizures cause sudden jerking movements, like your whole body jumps.

The type of seizure you have matters because it affects which medicines work best and what precautions you need to take.

What causes epilepsy

In about half of people diagnosed with epilepsy, doctors never find a specific cause. The brain simply misfires electrically in a way that runs in families or develops for reasons that are not yet understood. This is called idiopathic epilepsy.

In the other half, a cause can be identified. Common causes include a head injury (especially a severe one), a stroke, a brain tumor, an infection like meningitis, or a birth defect that affects how the brain is wired. Some people develop epilepsy after a high fever in childhood. Others have a genetic condition that makes seizures more likely. In older adults, stroke is the most common cause of newly diagnosed epilepsy.

Knowing the cause does not always change the treatment, but it can help your doctor predict which medicines might work and whether seizures might eventually stop on their own.

How epilepsy is treated

The first step is usually medicine. Anti-seizure medications (also called anticonvulsants) work by calming down the electrical misfiring in your brain. There are many different types, and finding the right one—or the right combination—sometimes takes trial and adjustment. Some people become seizure-free on the first medicine they try. Others need to try two or three before finding one that works without side effects they cannot tolerate.

If medicine does not control your seizures after trying two or more drugs, your neurologist might discuss other options. Brain surgery can be an option if tests show that seizures always start in one specific area of the brain that can be safely removed. Vagus nerve stimulation is a device (similar to a pacemaker) that sends electrical pulses to a nerve in your neck to help prevent seizures. Ketogenic diet—a high-fat, low-carbohydrate diet—can reduce seizures in some people, especially children.

Beyond medicine, many people benefit from identifying and avoiding their triggers. Common triggers include lack of sleep, stress, flashing lights, or missing doses of medicine. Keeping a seizure diary—writing down when seizures happen and what happened before—can help you spot patterns.

Living with epilepsy

Epilepsy affects different people differently. Some people have one seizure a month. Others go years without one. Some people's seizures stop completely after a few years of medicine, and they may eventually be able to stop taking it. Others need to take medicine for life.

Safety is an important consideration. Driving laws vary by state, but most require you to be seizure-free for a certain period (often three to six months) before you can drive. Swimming and bathing require precautions—never alone, and with someone nearby who knows what to do if a seizure happens. Contact sports may or may not be safe depending on your seizure type and how well controlled they are.

Many people with epilepsy work full-time, attend school, and live independently. The condition is manageable, and new medicines and treatments are being developed. A neurologist can help you understand your specific situation and what to expect.

Frequently Asked Questions

Can epilepsy go away on its own?

Yes, in some people. Children with certain types of epilepsy often outgrow it. Some adults become seizure-free after a few years of medicine and may eventually stop taking it under their doctor's supervision. However, others need to take medicine for life. Your neurologist can discuss the likelihood based on your specific type of epilepsy.

Is epilepsy hereditary?

Some types of epilepsy run in families, but having a parent or sibling with epilepsy does not mean you will develop it. Genetics play a role in some cases, but many people with epilepsy have no family history. Your doctor can discuss your personal risk based on your family background.

What should I do if someone is having a seizure?

Stay calm and keep them safe. Move dangerous objects away, cushion their head, and turn them on their side if possible so they can breathe. Do not put anything in their mouth or try to hold them down. Most seizures stop on their own within a few minutes. Call 911 if the seizure lasts longer than five minutes, if another seizure starts right after, or if you are unsure what to do.

Can I work or go to school with epilepsy?

Yes. Most people with epilepsy work and attend school. You may need to disclose your condition to your employer or school so they can make reasonable accommodations if needed, like allowing you to take medicine on schedule or providing a safe place to rest after a seizure. Laws protect you from discrimination based on epilepsy.

Will anti-seizure medicine make me drowsy?

Some medicines cause drowsiness, especially when you first start them or at higher doses. Others do not. If a medicine makes you too drowsy to function, tell your neurologist—there are many options, and they can adjust your dose or try a different medicine. Finding the right fit sometimes takes time.