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Seizure

A seizure is abnormal electrical activity in your brain. It causes changes in awareness and muscle control. It also causes symptoms that affect your behavior and senses. Seizures can affect anyone at any age and there are a lot of possible causes, from an underlying medical condition to an injury or illness. Treatment options are available to help you manage the frequency and severity of seizure symptoms.

Overview

Neural networks in your brain transmit signals. Seizures disrupt this electrical flow
When seizures happen, the flow of electrical signals in your brain is disrupted.

What is a seizure?

A seizure (pronounced “see-zhr”) is a surge of abnormal electrical activity in your brain. The most recognizable symptoms of a seizure are a temporary loss of consciousness and uncontrollable movements (convulsions).

Not all seizures look the same. You might stop what you’re doing and stare off into space for a few seconds. You might jerk your arm or feel your muscles twitch. You might only have one seizure in your life or have multiple seizures per day. Your experience with seizures can be very different from someone else’s.

There are many possible causes of seizures because a lot of things can interfere with your brain’s typical electrical patterns. These range from changes to your blood sugar levels to an illness, injury or underlying condition.

A healthcare provider can help you find the right treatment for your needs.

What are the types of seizures?

There are two main types of seizures:

  • Generalized seizures (generalized onset seizures): Electrical activity starts on both sides of your brain at the same time. You may shake both sides of your body, shake one side or only stare and stop what you’re doing. Usually, it affects kids or young adults, but it can occur at any age.
  • Focal seizures (focal onset seizures): Electrical activity begins on one side or “focus” of your brain. Symptoms usually affect one side of your body and may or may not affect your awareness. This means that you may or may not remember the seizure. Focal seizures may stay focal or may spread to both sides.

Generalized seizure types

The types of generalized seizure disorders include:

  • Absence seizures: You stop what you’re doing and have a blank stare.
  • Atonic seizures (drop seizures): You lose muscle control and drop to the ground suddenly.
  • Clonic seizures: You’ll shake both sides of your body and pass out or shake one side and not pass out.
  • Myoclonic seizures: These involve a quick jerk or twitch that affects one muscle or a group of connected muscles.
  • Secondary generalized seizures: You have a focal seizure (electrical activity starts in one part of your brain) followed by a generalized seizure (electrical activity spreads to both sides of your brain).
  • Tonic-clonic seizures: Your muscles stiffen, you lose consciousness and have convulsions.
  • Tonic seizures: You pass out and your muscles tighten up but you don’t have convulsions.

Focal seizure types

The types of focal seizure disorders include:

  • Focal onset aware seizures (simple partial seizure): You’re aware of a seizure when it happens and able to remember it.
  • Focal onset impaired awareness seizures (complex partial seizure): You lose awareness and experience confusion when the seizure happens and can’t remember the seizure.

How common is a seizure?

Up to 10% of people around the world will have at least one seizure during their lifetimes.

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Symptoms and Causes

What are the symptoms of a seizure?

Seizure symptoms vary based on the type and severity, but may include:

Other symptoms may include:

  • Sudden emotional changes (confusion, fear, joy, anxiety).
  • Teeth clenching.
  • Drooling.
  • Abnormal eye movements.
  • Loss of bladder or bowel control.
  • Noise making (grunting or snorting).

These symptoms are temporary and only last for a few seconds to minutes.

What are the stages of a seizure?

The stages or phases of a seizure include:

  1. Prodrome phase: Before a seizure, you may notice mood or behavioral changes, feel lightheaded or have trouble focusing. Days before a seizure, you may have trouble sleeping.
  2. Aura phase: Right before the first symptoms of a seizure start, you may notice vision changes, a headache, dizziness, nausea, anxiety or fear, and changes to your senses (like taste, sound, smell and feeling).
  3. Ictal phase: This is when a seizure happens. You’ll experience seizure symptoms.
  4. Postictal phase: Immediately after a seizure ends, you may feel confused, exhausted, sore, strong emotions and more.

Not everyone who has a seizure experiences all phases, especially the aura. Many seizures come on suddenly and you’re unaware of any early signs.

What are the warning signs of a seizure?

Warning signs of a seizure may include:

  • Sensory symptoms: Seeing bright lights or distortions in how objects appear, hearing unexpected sounds, sudden unexpected tastes (metallic or bitter) or smells and strange feelings on your skin (numbness or tingling).
  • Emotional changes: Strong emotions like fear or joy, déjá vu (when a new experience somehow feels familiar) or jamais vu (when a familiar experience somehow feels new).
  • Autonomic symptoms: These affect body systems that your brain runs automatically, like sweating, making too much saliva (drooling), an upset stomach and pale skin.

Not everyone experiences warning signs before a seizure.

What causes a seizure?

A surge of electrical activity in your brain causes a seizure.

Neurons (nerve cells) communicate by sending electrical signals to different parts of your brain. When a seizure happens, the affected brain cells fire signals uncontrollably to others around them. This kind of electrical activity overloads the affected areas of your brain and causes seizure symptoms.

Seizure causes fall into two main categories depending on why they happen:

  • Provoked seizures (nonepileptic): A trigger, which could be a temporary condition or certain circumstances, causes seizure symptoms to happen.
  • Unprovoked seizures (epileptic): Seizures happen spontaneously (randomly). They may happen often. These seizures are the primary symptom of epilepsy.

Seizures without a known cause are called idiopathic seizures.

Seizure triggers

The following may trigger a seizure:

Triggers are different for each person. If you have seizures regularly, you may want to keep track of what you were doing before a seizure took place. A healthcare provider can review this information with you to determine your triggers.

Conditions that cause seizures

Seizures can happen for many different reasons. These include but aren’t limited to the following:

Other conditions that can cause seizures may include:

What are the risk factors for a seizure?

Anyone at any age can have a seizure. You may be more at risk if you:

  • Have an underlying medical condition.
  • Have a biological family history of seizures.
  • Are a child (under 18 years).
  • Are over age 50.

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What are the complications of a seizure?

Seizures often involve losing consciousness and passing out. When this happens, there’s a risk of injuries from falling or suddenly stopping what you’re doing at the time (like driving, operating machinery or climbing heights). Convulsions may cause you to smack your arms or legs on hard objects, causing cuts, bruises or broken bones.

Status epilepticus happens when a seizure lasts for more than five minutes or you have more than one seizure without enough time between them to recover. Status epilepticus is a life-threatening medical emergency because it can cause brain damage or even death.

Seizures and mental health

Seizures can significantly impact your mental health. It’s also common to have symptoms of anxiety and depression with seizures.

This may happen because seizures are distracting and can pull you away from the activities you enjoy. You may feel anxious or fearful of having another seizure. You may keep yourself up at night worrying about when the next one might happen. You might avoid going out in public or spending time with loved ones if you’re embarrassed about having a seizure in front of others.

Seizures happen outside of your control, so it’s normal to have these feelings. A mental health professional can help you manage how seizures affect your emotional well-being.

Diagnosis and Tests

How is a seizure diagnosed?

A healthcare provider, usually a neurologist, will diagnose a seizure after a physical exam, neurological exam and testing. During the exams, your provider will learn more about your symptoms and review your medical history and family health history.

It often helps to have someone with you during your appointment who witnessed the seizure to explain what they noticed, as you might not remember what happened.

What tests diagnose a seizure?

Tests may help confirm whether you had a seizure and — if you did — what might have caused it.

A key part of diagnosing seizures is finding if there’s a focal point — a specific area in your brain where your seizures start. Locating a focal point can help your provider plan for treatment.

Tests to diagnose seizures include:

Providers might also recommend tests if they suspect injuries or complications from a seizure. Your provider will tell you (or someone you choose to make medical decisions for you) what tests they recommend and why.

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Management and Treatment

How is a seizure treated?

Seizure treatment varies based on the type, severity and cause. Your healthcare provider may recommend the following:

  • Managing any underlying causes or conditions: Your provider will first treat any underlying conditions — like a stroke or low blood sugar. This may prevent future seizures.
  • Taking antiseizure medications: Medications may help prevent seizures or decrease how often they happen.
  • Surgery: Surgery may reduce seizure frequency and severity by addressing the area of your brain where seizures start (focal point).
  • Brain stimulation: A surgeon will implant a device into your brain to deliver a mild electrical current. The current interferes with and tries to stop abnormal electrical activity. There are different types of brain stimulation available, like vagus nerve stimulation.

If certain types of treatment aren’t successful, your provider may recommend changing the foods you eat. A low- or no-carb (ketogenic) diet may reduce how often you have seizures. Studies are ongoing to learn more about the effectiveness of dietary changes in relation to seizures.

Seizure medications

Medications can help you manage seizures by:

  • Stopping a seizure as it happens.
  • Preventing future seizures.
  • Reducing the severity of seizures.
  • Reducing the frequency of seizures.

Common medications for seizures include but aren’t limited to the following:

A healthcare provider will offer regular follow-up appointments after you start taking a new medication to measure its effectiveness. It could take several months before you and your provider find the medication and dosage that’s right for you. Always continue taking your medications as directed, even if you feel better.

Studies show that an estimated 33% of people who take antiseizure medications notice that seizure symptoms completely stop. Another 33% say they see less frequent symptoms after taking antiseizure medications.

Prevention

Can a seizure be prevented?

Seizures are unpredictable, so it’s not possible to completely prevent them. The best thing you can do is avoid possible causes or triggers, like managing blood glucose levels or protecting yourself from illness and injury.

Outlook / Prognosis

What can I expect if I have a seizure?

Fewer than half of people who have a single, unprovoked seizure will have another. If a second seizure happens, healthcare providers may recommend starting antiseizure medications. For provoked seizures, the risk of having another depends on what caused the first seizure. If it’s treatable, your risk of having another seizure is low (unless you have a repeat of the circumstances that caused the first seizure).

Medications may prevent seizures or reduce how often they happen. However, it sometimes takes trying multiple medications (or combinations of them) to find one that works best.

In some cases, seizures may be more difficult to treat with medications alone. A provider may recommend surgery, following a specific meal plan or other treatment options.

If seizures happen often, your provider can help you take precautions to stay safe. You may choose to wear a medical ID bracelet or carry a medical ID card with you so others will know what to do in the event of a seizure.

How long does a seizure last?

Seizure symptoms usually last for a few seconds to minutes, up to 15 minutes. Symptoms can last longer if you have several seizures, one after the other (this is a medical emergency).

What’s the outlook for a seizure?

Each person’s experience with seizures is different, so the outlook can vary widely. Your outlook may depend on several factors. These include:

  • Is there a known cause?
  • Is the cause manageable or treatable?
  • What type of seizure did you have?
  • How severe was the seizure, and how long did it last?
  • Was this your first seizure?
  • Do you have an underlying condition where seizures are a common symptom?
  • What treatment options are available to help you manage this seizure type?

Your healthcare provider will have the most up-to-date information on what you can expect. Let them know if you have any questions.

Living With

When should I see a healthcare provider?

You should go to the emergency room if you have a first-time seizure or if you have any event that makes you pass out and you don’t know what caused it. If you’re alone and have what you think is a first-time seizure, you should call or see a provider right away.

If you had one seizure in the past, it’s important to watch for signs of another. If you have a second seizure, seeing a healthcare provider as soon as possible is very important. Seizures cause changes in your brain that make it easier to have more seizures, so early diagnosis and treatment are key.

Calling an ambulance after a seizure may be unnecessary if a person has seizures regularly. However, even if you know why you had a seizure, you may have injuries that need medical attention.

What questions should I ask my healthcare provider?

If you have a seizure, you may want to ask your healthcare provider:

  • What caused this seizure?
  • How do I avoid triggers?
  • What type of treatment do you recommend?
  • Are there side effects of the treatment?
  • Will another seizure happen again?
  • How do I keep myself safe?

Additional Common Questions

What types of seizures affect children?

Childhood seizures are possible and happen for many of the same reasons why adults have seizures. Common types of childhood seizures and seizure disorders include, but aren’t limited to, the following:

Is it safe to become pregnant if I have seizures?

Yes, it’s possible to have a safe pregnancy if you have seizures. A healthcare provider may recommend frequent checkups to monitor your and the fetus’s health. Some antiseizure medications aren’t safe to take while pregnant, so a provider will offer safer alternatives to help you manage symptoms. Your healthcare provider is the best person to talk to if you have any questions or concerns.

A note from Cleveland Clinic

Seizures may seem like events in dramatic television shows or movies, but they could be an everyday or frequent occurrence for you or a loved one. They’re unpleasant to experience and even scarier to watch. You may not feel like yourself before, during and after a seizure and you’ll likely need time to recover.

Even though seizures are out of your control, a healthcare provider can help you get ahead of symptoms. Your provider may recommend management techniques for an underlying condition, or they’ll help you find ways to identify and avoid triggers. Medications can be very helpful to reduce recurring seizures and surgery may be an option if other treatment types don’t work well.

If you have any questions about what to expect or how to keep yourself or a loved one safe in the event of a seizure, don’t hesitate to contact a healthcare provider.

Medically Reviewed

Last reviewed on 07/15/2024.

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