A person having a seizure may experience muscle spasms, blink rapidly, fall to the ground, or lose consciousness. After a seizure, a person may feel weak, tired, and confused.

Seizures may occur as a side effect of a health condition that originates from the brain, such as epilepsy. They will require medical diagnosis of and treatment for the underlying cause of seizures.

Nonepileptic seizures may occur as well. These vary in type and may affect individuals with curable or reversible health conditions.

Other catalysts for seizures include:

  • high fevers
  • infections
  • head injuries
  • strokes
  • certain drugs

This article will discuss in further detail the symptoms and types of seizures, their causes, the aftereffects, and more.

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Sometimes, people will experience certain sensations, called an aura, prior to a seizure. These symptoms result from electrical changes in the brain that occur when the seizure starts.

They act as a warning that a seizure will happen. Yet the exact symptoms will depend on which part of the brain the seizure starts in.

According to John Hopkins Medicine, an aura typically occurs before a focal seizure, especially a complex focal seizure. The most common aura involves feelings such as:

  • déjà vu
  • impending doom
  • fear
  • euphoria

People may also experience visual changes, hearing abnormalities, or changes in their sense of smell prior to having a seizure.

If a person notices any of these symptoms, they may want to keep track of them. Recording details of symptoms and when they happen can help a doctor diagnose and treat seizures.

Symptoms can vary depending on the type of seizure an adult has, but they may include:

  • losing consciousness
  • falling to the ground
  • rapid eye movements
  • drooling or foaming at the mouth
  • clenching of the teeth or jaw
  • experiencing incontinence
  • having uncontrollable muscle spasms
  • staring
  • having trouble talking

Seizures may last a few minutes. However, the Centers for Disease Control and Prevention (CDC) encourage people to call 911 if:

  • a seizure lasts longer than 5 minutes
  • an injury related to the seizure occurs
  • the person has never had a seizure before

Babies can also have seizures. However, a person may have more difficulty recognizing them because a baby’s healthy, typical responses may look similar to symptoms of a seizure.

Newborns commonly jerk, twitch, or contort their faces into grimacing expressions. So, a person can easily mistake these movements for seizures or not recognize them as seizure symptoms at all.

Seizure symptoms may include any or all of the following:

  • spasmodic stiffening of the arms or legs, which can alternate from side to side
  • a jerking upward of whole upper body or a jerking of both legs toward the belly
  • changes to facial expressions, breathing, or heart rate

According to the University of Chicago Medicine, seizures are particularly likely if a baby repeats the same movements for approximately the same duration at the same time of day, usually when waking up or going to sleep. For babies prone to seizures, symptoms commonly occur every day.

In general, research suggest that genetics play an important role in whether a baby will experience seizures.

According to a 2018 research review, one-third of children with febrile seizures have a family history of seizures. The risk of a baby having febrile seizures is around 20% with an affected sibling and 33% with affected parents.

After a seizure, a person may experience a variety of effects that may persist for several minutes or even hours.

According to the National Institute of Neurological Disorders and Stroke, people may feel tired, weak, and confused after a seizure has ended. Other common symptoms include headaches or pain in the muscles that contracted during the seizure.

The specific aftereffects that a person experiences can help a healthcare professional determine which part of the brain seizure originated in.

One example is Todd’s paralysis, a temporary paralysis in part of the body due to the area of the brain the seizure originated in. If the seizure stemmed from the temporal lobe, a person is more likely to experience language or behavioral changes.

According to the CDC, two main types of seizures exist: focal onset and generalized onset.

Generalized seizures affect both sides of the brain, and they include absence seizures and tonic-clonic seizures. These types of seizures produce many common seizure symptoms, such as:

  • rapid eye movement
  • loss of consciousness
  • muscle spasms
  • crying out
  • falling to the ground

Focal seizures, or partial seizures, originate in just one area of the brain. Subcategories of focal seizures include:

  • Focal aware seizures: These affect a small portion of the brain and often cause twitching or changes in sensation, such as vision, feeling, scent, or taste.
  • Focal unaware seizures: These seizures can cause people to feel dazed or confused. A person may lose the ability to speak or process language for several minutes after this type of seizure has occurred.
  • Secondary generalized seizures: These seizures begin in one part of the brain but spread to other parts of the brain as they progress, leading to a tonic-clonic seizure.

People with epilepsy may experience all these types of seizures.

Psychogenic nonepileptic seizures may also occur, due to psychological distress. Though these are not epileptic seizures, they have similar symptoms.

These symptoms include:

  • coming in and out of consciousness
  • shaking of the body and head
  • tightly closed eyes

Research suggests the most common cause is a conversion disorder. This occurs when a person has the symptoms of a health condition without an actual underlying condition or injury.

Nerve cells in the brain send electrical signals to communicate. Any change to this electrical activity can cause seizures. Factors that can cause abnormal electrical activity include:

  • electrolyte imbalance
  • high fever
  • withdrawal from drugs or alcohol
  • concussion
  • high or low blood sugar levels

According to a 2021 article, genetics play a role in whether a person will experience epilepsy. The article also lists other potential causes for seizures:

With a treatable underlying cause, such as hypoglycemia, seizures are not likely to reoccur after treatment.

For epilepsy specifically, the CDC states that the condition is most likely to develop in children under age 2 and adults over age 65.

Not every seizure is an emergency, and while they can be fatal, the CDC states that most people can live safely with seizures. Seizures may turn life threatening if:

  • They put a person at risk of falling heavily, choking, or drowning.
  • They result from a serious health condition, such as stroke or brain tumor.
  • They last longer than 5 minutes.

Although very rare, sudden unexpected death in epilepsy (SUDEP) does occur. This refers to deaths that have no other cause than the seizure itself.

SUDEP is the cause of death in roughly 1.16 out of every 1,000 people with epilepsy.

If a person experiences a seizure for the first time, they will need prompt medical attention. A doctor can then diagnose the underlying cause and suggest appropriate treatment.

If a person experiences subsequent, more severe seizures, they should also seek medical help. A doctor can analyze patterns, discuss any aftereffects, and reevaluate treatment to help reduce the severity of seizures.

People who experience seizures may find it helpful to record the details of each episode to report to their doctor.

If people witness someone having a seizure, they will need to call 911 for any seizure that lasts longer than 5 minutes, according to the CDC, or if any injury occurs during the seizure.

Seizures may be epileptic or nonepileptic, and they stem from a disruption in nerve cell activity in different parts of the brain. Seizures typically last for only a few minutes at a time.

A person may experience various symptoms before, during, and after a seizure.

Tracking specific symptoms of a seizure may help a doctor diagnose or adjust treatment for seizures. Learning to recognize the warning signs of a seizure can also help people get into a safe space before a seizure occurs.

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