Evaluation of First-Time Seizure

Seizures can be a sign of epilepsy, but they can happen for other reasons as well. Although the exact cause of a seizure can't always be pinpointed, you should always be evaluated by a doctor the first time you have a seizure. It’s important to know if you have an underlying health condition, such as epilepsy, that needs to be treated to prevent future seizures.

Facts about seizures

When your brain's electrical system doesn't work properly, a seizure occurs. Usually, your brain cells shoot off electrical impulses in a particular way. Certain factors can make those electrical impulses fire erratically, essentially resulting in a "short circuit" in your brain that causes a seizure.

Seizures are classified by type and each has different symptoms. You may have a seizure that lasts for under a minute and causes no lasting effects, or a seizure that lasts for a few minutes and causes symptoms that last for a short time. Why the brain suddenly misfires and causes a seizure is not usually identified, except when it occurs in infants and older adults. Sometimes, health conditions, such as a tumor, a brain infection, or developmental problems, may be responsible for seizures.

About 1 to 2 percent of all visits to the emergency room are because of seizures. Usually, a first seizure happens before age 25.

Types of seizures

Seizures are often grouped by the amount of brain tissue that's involved. These are the major types of seizures:

  • Partial seizures

  • Spasms in infants

  • Absence seizures, or petit mal seizures 

  • Myoclonic seizures

  • Atonic seizures

  • Generalized tonic-clonic or grand mal seizures


Symptoms can vary widely based on the type and severity of the seizure. These are common symptoms:

  • Staring blankly

  • Repetitive motions, such as smacking your lips

  • Uncontrollable movement of the eyes

  • Loss of consciousness

  • Loss of bladder and/or bowel control 

  • Convulsions and jerking

  • Tremors or twitching

  • Confusion

Diagnosing the seizure

Your doctor will first make sure that you're getting enough oxygen, that all of your vital signs are normal and healthy, and that there are no signs that the seizure is still happening. The primary goal of the medical evaluation is to figure out if your symptoms were actually caused by a seizure and, if so, why the seizure occurred.

To make a diagnosis, your doctor may perform or order:

  • Complete neurological exam

  • Blood work and other lab tests to look for abnormalities in blood glucose and other factors

  • Imaging tests of the brain, such as an MRI or CT scan

  • Electroencephalogram, to test your brain's electrical activity

Your doctor will also ask a series of questions to find out if any of these factors may be responsible for the seizure:

  • Drug or alcohol use

  • Injury to the head

  • High fever or infection

  • Genetic abnormality


Seizures can be treated in several ways. These are common treatments:

  • A special high-fat, low-carbohydrate diet called the ketogenic diet (often suggested for children)

  • Medications to control electrical activity in the brain

  • Surgery to repair abnormalities in the brain

  • Vagus nerve stimulation, which delivers electrical impulses to the brain

Calling the doctor

Any time a child or an adult has a seizure, call your doctor immediately for an evaluation. Your doctor may be able to find a health problem or abnormality that caused the seizure and recommend appropriate treatment.


Seizures can happen at any time. If you're driving, operating a dangerous machine, or standing at the top of a staircase, you could be seriously injured during your seizure.

Key points to remember

Although seizures usually aren't serious, that doesn't mean that they don't need to be evaluated by a doctor. Seizures can often be successfully treated so that they don't interfere with your life.