What Is the Main Cause of a Seizure?

Medically Reviewed on 11/14/2022
What Is the Main Cause of a Seizure
In adults, the main cause of a seizure is epilepsy

A seizure can be caused by anything that interrupts the normal communication between brain cells and causes abnormal electrical activity in the brain. Normal electrical activity of the brain involves coordinated electrical signals from neurons in different areas of the brain. During a seizure, however, several neurons fire electrical signals at the same time.

In adults, the main cause of a seizure is epilepsy. In newborns, the most common cause of seizures is low oxygen supply to the brain, also called hypoxic-ischemic encephalopathy. In children, the most common causes of seizures are high fever and electrolyte imbalance.

What are other causes of seizures?

Other causes of seizures include:

What are the symptoms of a seizure?

A seizure refers to unusual electrical activity in the brain that can lead to changes in movement, behavior, or emotions. Symptoms of a seizure may vary depending on the type of seizure and the age group it affects. 

Although the terms seizures and convulsions are used interchangeably, not all seizures are convulsive. A convulsion involves uncontrollable, rapid, and rhythmic shaking and occurs due to repeated contractions and relaxations of muscles. 

Many times, warning signs or prodromal symptoms may occur before a seizure starts. These may include:

  • Anxiety
  • Restlessness
  • Vertigo
  • Nausea
  • Visual symptoms, such as seeing bright lights, zigzag lines, or spots

Seizure symptoms typically begin suddenly and may include:

  • Staring blankly at a point
  • Confusion
  • Eye flutters
  • Abnormal sounds, such as snorting or grunting
  • Frothing or drooling from the mouth
  • Loss of bowel or bladder control
  • Abnormal taste sensations (such as a bitter or metallic taste)
  • Teeth grinding, chewing, or clenching
  • Finger rubbing
  • Lip smacking
  • Sudden mood changes, such as anger, fear, laughter, or panic
  • Jerking movements of the limbs
  • Sudden falls

In some people, seizure symptoms may be too subtle to notice. For example, they may experience a brief blackout followed by confusion and an inability to recall what happened.

Seizure symptoms generally last for no more than a few seconds to minutes. Rarely, they may continue for longer, generally for up to 15 minutes.


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How are seizures diagnosed?

Diagnosis of seizures involves taking a detailed medical history and performing a physical examination, including a neurological exam. Tests may be ordered to make a definitive diagnosis of seizures:

  • Blood tests to check for electrolyte imbalances, blood sugar levels, liver and kidney dysfunction, and signs of infection
  • Electroencephalogram to study the electrical activity of the brain
  • Brain MRI or CT scan to obtain detailed images of the brain
  • Lumbar puncture and cerebrospinal fluid examination
  • Positron emission tomography scan in the case of a suspected brain tumor
  • Single-photon emission computerized tomography to assess blood flow to the brain during a seizure

What is the treatment for seizures?

Seizure treatment depends on the type, cause, severity, and frequency of the seizures. If you are having seizures for the first time and are pregnant, your doctor will recommend treatment that is safe for you and your baby.

Treatment may include a combination of medications and lifestyle modifications:

  • Surgery for brain tumors or those that do not respond to conservative treatment may be needed in some cases. 
  • Certain factors, such as alcohol, stress, lack of sleep, heat, or menstrual periods, can trigger seizures. Your doctor can help you manage r avoid these triggers to reduce the frequency of seizure episodes. 
  • Since a seizure disorder can pose a threat to your safety and mental health, psychiatric counseling may be recommended to help you manage your disease and lead a fulfilling life.
Medically Reviewed on 11/14/2022
Image Source: iStock image

Seizures. https://kidshealth.org/en/parents/seizure.html

Seizure. https://www.ncbi.nlm.nih.gov/books/NBK430765/

Patient education: Seizures in adults (Beyond the Basics). https://www.uptodate.com/contents/seizures-in-adults-beyond-the-basics#H8