Causes and Prevention of Seizures

Seizures are episodes characterized by involuntary movements, changes in consciousness, or both. They are more likely to occur when a person has epilepsy, a disorder involving abnormal brain activity. They can, however, occur unexpectedly and without epilepsy.

The primary causes of non-epileptic seizures are illness, injury, recreational drug use, and medication or alcohol withdrawal.

This article discusses the causes of epilepsy and other concerns that can lead to seizures. It also covers how to prevent seizures and recognize their triggers.

Brain scan images captured via MRI
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Epilepsy

Epilepsy has many causes that can be hereditary (run in your family) or congenital (affecting you from birth). It can also happen after an injury or medical condition, such as brain trauma, a stroke, vascular malformations, brain infections, and tumors.

However, for many people with epilepsy, a cause cannot be identified, even after an extensive medical evaluation.

Hereditary epilepsy runs in families. People with hereditary epilepsy often develop their first seizure within the first two decades of life.

In congenital epilepsy, a child is born with the predisposition to have epilepsy. This may or may not be hereditary. The seizures characteristic of congenital epilepsy generally begin early in life.

If you have seizures, your healthcare provider may order a brain magnetic resonance imaging (MRI) scan, imaging that forms a detailed picture of the brain. This may show if there are any areas of damage making you more likely to have seizures.

You might also have an electroencephalogram (EEG), a brain wave test that evaluates the function of the brain. It may show whether you have abnormal electrical activity that's typical of seizure disorders. Yet, for some people with epilepsy, these tests can be completely normal.

Head Trauma and Brain Injury

Severe head trauma may produce sudden seizures at the time of trauma. It may also cause brain injuries that result in long-lasting epilepsy. 

Some brain injuries cause seizures because of bleeding and scars inside the brain, which may interfere with the brain's normal electrical activity. This produces cerebral (brain) hyperactivity or erratic nerve stimulation that generates a seizure.

Medical Illnesses

Several other medical conditions can also interfere with the brain's function, resulting in seizures.

These conditions may cause seizures that occur until the illness is gone. However, they may also cause a lasting seizure disorder that continues even after the illness ends.

Brain tumors: Cancer that starts in the brain or spreads there from elsewhere in the body can cause swelling and pressure in the brain. This can disrupt the brain's normal activity and cause seizures.

Seizures may be the first sign that a person has cancer in or near the brain. Sometimes, once the cancer is removed, the seizures stop.

Ischemic stroke: Strokes cause small or large areas of brain infarct (tissue damage). These areas may produce seizures by preventing areas of the brain from functioning normally. 

Strokes in certain areas of the brain are more likely to cause a seizure disorder. For example, a stroke in the temporal lobe is more likely to cause one than a stroke in the brainstem.

Hemorrhage: Brain hemorrhage (bleeding in or around the brain) can cause irritation of the brain tissue, which results in seizures. In general, hemorrhagic strokes are more often associated with seizures than ischemic strokes, which are due to a lack of blood flow to the brain.

Encephalitis/brain abscess: Encephalitis is an inflammation or infection of the brain tissue. A brain abscess is an enclosed infection in the brain. These are both uncommon types of infection. However, they are relatively serious and may produce immediate seizures, as well as lasting epilepsy. 

Meningitis: An infection of the meninges (protective layers that surround the brain) may disrupt brain activity, resulting in a seizure. Most of the time, seizures that are associated with meningitis resolve once the infection is treated. However, some severe cases may result in epilepsy.

Metabolic problems: Extreme electrolyte imbalances and liver and kidney failure can disrupt the activity of the neurons in the brain. This causes overactivity of the neurons, which causes seizures. 

The seizures that result from electrolyte abnormalities and organ failure often do not continue once the medical problem is resolved.

Fevers: Very high fevers can cause seizures, particularly in young children and babies. These types of seizures are called febrile seizures.

If your child has a febrile seizure, you need to get them prompt medical attention. Having a febrile seizure does not necessarily mean your child will go on to have seizures or epilepsy when they're older.

Substance Use

Seizures can also be caused by issues relating to substance use. These are medical emergencies that require immediate attention. Inform the medical team of the substance involved so that you can get the right treatment in a timely manner.

Substance-related causes of seizures include:

Alcohol withdrawal: Often, alcohol withdrawal, which is the body's reaction to the abrupt discontinuation of alcohol after heavy use, can cause seizures. This reaction can be dangerous.

Use of illicit drugs: Many recreational drugs are associated with seizures. This response is somewhat unpredictable. It can happen even if you've used a particular drug without having had associated seizures in the past.

Drug withdrawal: Withdrawal from certain pharmaceutical or recreational drugs, which is the abrupt discontinuation of drugs after heavy use, can also cause seizures. 

For example, seizures can occur with the abrupt withdrawal of the prescription drug Wellbutrin (bupropion), a drug used for depression and smoking cessation.

What Triggers a Seizure?

Seizure triggers are events or circumstances that may provoke seizures and cause problems if you have epilepsy. Knowing and avoiding these triggers is important to reduce your seizure risk.

Common seizure triggers include:

Alcohol intake: Many people who have epilepsy experience seizures whenever they consume alcohol. This can happen even if the epilepsy is well-controlled with medication.

Alcohol can alter the electrical activity in the brain in a manner that triggers seizures. It can also interfere with metabolism of anticonvulsants, preventing the medicine from working properly.

Lack of sleep: Fatigue from lack of sleep or from inadequate sleep is also a well-known trigger of seizures. In fact, a sleep-deprived EEG is one of the tests used to evaluate seizure disorders.

A sleep-deprived EEG is obtained after a period of deliberate lack of sleep. If you have epilepsy, a seizure is most likely to occur during the sleep-deprived state. This makes the EEG confirmation of seizure activity more likely, which assists in diagnosis and treatment. 

Sleep-deprived EEGs are always done under close medical supervision so that the seizure can be safely controlled.

Flashing lights: Photosensitive seizures are those that are triggered by rapidly flashing lights. This type of seizure isn't common and is more often a problem if you have epilepsy. However, the resulting seizures can be quite severe.

Stress, weather changes, certain smells: Most people who have epilepsy also notice specific triggers, such as stress, exposure to certain odors, and even weather changes. The evidence about these factors as causes of seizures is not consistent, and the triggers differ for each individual.

You can help manage epilepsy by learning to identify and recognize personal triggers and avoiding them as much as possible.

Seizure Prevention

Seizures can result in socially awkward situations, physical injury, car accidents, and dangerous falls. Whenever possible, it is best to prevent seizures.

There are two main approaches to seizure prevention—medication use and trigger avoidance.

Sticking to Your Medications

Anticonvulsants are the most effective way to avoid having seizures if you have epilepsy. Many anticonvulsant medications can effectively control seizures. Your healthcare provider will help you decide which anticonvulsant or combination of anticonvulsants can help you.

Taking anti-seizure medications regularly is also an important part of seizure control. If you are taking anticonvulsants, you should take them as directed and at approximately the same time every day.

Maintaining a regular schedule is the best way to maintain an even level of anticonvulsant levels in your body. In general, anti-seizure medication effects can last between eight and 48 hours, depending on the drug.

Let your healthcare provider know if you experience side effects from taking anticonvulsants or are dissatisfied with them in any way.

You should not stop taking an anticonvulsant without discussing it with a healthcare provider. Suddenly discontinuing your anticonvulsant medications can provoke seizures.

Your healthcare provider may advise you to slowly taper off of the anticonvulsant or replace it with another one. That can help ensure you won't experience a seizure triggered by medication withdrawal.

Trigger Avoidance

If you have been diagnosed with epilepsy, it is important to maintain lifestyle habits that avoid your known seizure triggers.

This means getting enough sleep, not drinking alcohol, and avoiding flashing bright lights or other triggers you've noticed.

It may take some time for you to notice everything that triggers you. Keeping a log of your seizures and what was happening just before them can be helpful in identifying patterns.

Take Note of Auras

Some people may notice a temporary neurological disturbance prior to their seizure called an aura. Some common auras include feelings of déjà vu, nausea, smelling something like burnt rubber, or having an odd taste in your mouth. Auras can tip you off that a seizure is about to happen. By noticing them, you can take steps to get yourself out of harm's way (e.g., sit down so you don't fall).

Summary

Seizures are likely to occur with a seizure disorder called epilepsy. For those without epilepsy, seizures can be caused by a number of factors. Some are not easy for you to predict or prevent, such as encephalitis or electrolyte imbalance. Some, such as drug withdrawal, are preventable.

If you've been diagnosed with epilepsy, the best ways to prevent seizures are by taking anticonvulsant medications and avoiding seizure triggers. Be sure to take your prescribed medication regularly and as directed.

A Word From Verywell

Epilepsy is a medical condition that impacts your lifestyle. However, it is something that you learn to manage with help from your healthcare provider.

Be open with your provider about what you are experiencing and how epilepsy is impacting your quality of life so that any necessary changes to your treatment plan can be made to both prevent seizures and help you live your best life.

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12 Sources
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