First Time User? Enroll now.
Find Vaccine information, visitor restrictions, and additional resources
Home > Health Library > Seizures
The brain controls how the body moves by sending out small electrical signals through the nerves to the muscles. Seizures, or convulsions, occur when abnormal signals from the brain change the way the body functions.
Seizures are different from person to person. Some people have only slight shaking of a hand and do not lose consciousness. Other people may become unconscious and have violent shaking of the entire body.
Shaking of the body, either mild or violent, does not always occur with seizures. Some people who have seizures have symptoms before the seizure (auras) or briefly lose touch with their surroundings and appear to stare into space. Although the person is awake, he or she does not respond normally. Afterwards, the person does not remember the episode.
Not all body shaking is caused by seizures. Many medical conditions can cause a type of body shaking that usually affects the hands and head (tremors).
A small number of people will have only one seizure during their lifetime. A single seizure usually lasts less than 3 minutes and is not followed by a second seizure. Any normally healthy person can have a single seizure under certain conditions. For instance, a sharp blow to the head may cause a seizure. Having one seizure does not always mean that a serious health problem exists. But if you have a first-time seizure, you should be checked by your doctor. It is important to rule out a serious illness that may have caused the seizure. Fever seizures (febrile convulsions) are the most common cause of a single seizure, especially in children. For more information, see the topic Fever Seizures.
Epilepsy is a nervous system problem that causes seizures. It can develop at any age. For more information, see the topic Epilepsy.
A seizure can be a symptom of another health problem, such as:
Eclampsia is pregnancy-related seizure activity that is related to high blood pressure. It is a life-threatening condition for both a mother and her baby (fetus) because during a seizure, the fetus's oxygen supply is drastically reduced. Eclampsia is more likely to occur after the 20th week of pregnancy. For more information, see the topic Preeclampsia and High Blood Pressure During Pregnancy.
Nonepileptic seizure (NES) is a condition that can cause seizure-like activity without having a central nervous system problem. NES can be related to a mental health problem. The physical symptoms may be caused by emotional conflicts or stress. The symptoms usually appear suddenly and at times of extreme emotional stress.
No matter what caused the seizure, you can help the person having a seizure.
A person who has had a seizure should not drive, swim, climb ladders, or operate machinery until he or she has seen a doctor about the seizure.
Treatment of a seizure depends on what has caused the seizure.
Check your symptoms to decide if and when you should see a doctor.
Health Tools help you make wise health decisions or take action to improve your health.
Many things can affect how your body responds to a symptom and what kind of care you may need. These include:
You have answered all the questions. Based on your answers, you may be able to take care of this problem at home.
Neurological symptoms—which may be signs of a problem with the nervous system—can affect many body functions. Symptoms may include:
Symptoms of serious illness may include:
Symptoms of serious illness in a baby may include the following:
Based on your answers, the problem may not improve without medical care.
Based on your answers, you need emergency care.
Call 911 or other emergency services now.
Sometimes people don't want to call 911. They may think that their symptoms aren't serious or that they can just get someone else to drive them. Or they might be concerned about the cost. But based on your answers, the safest and quickest way for you to get the care you need is to call 911 for medical transport to the hospital.
Based on your answers, you may need care right away. The problem is likely to get worse without medical care.
Based on your answers, you may need care soon. The problem probably will not get better without medical care.
If you witness a seizure, your account of the seizure will help a doctor diagnose and treat the person. Try to stay calm. Pay close attention to what happens during and after the seizure.
A person who has had a seizure should not drive, swim, climb ladders, or operate machinery until he or she has seen a doctor about the seizure and the doctor has said that the person is allowed to drive or operate machinery.
Call your doctor if any of the following occur during home treatment:
Note: If you think you may have a seizure disorder or are being evaluated for one, do not drive, operate heavy machinery, swim, climb ladders, or participate in other potentially dangerous activities until you have been specifically cleared to do these things by your doctor.
Many causes of seizures, such as some forms of epilepsy, cannot be prevented. But head injury is a common cause of seizures and epilepsy that you may be able to prevent. To prevent a head injury:
If you are being treated for a seizure disorder:
To prepare for your appointment, see the topicMaking the Most of Your Appointment.
You can help your doctor diagnose and treat your condition by being prepared to answer the following questions:
If possible, ask the person who witnessed your seizure to come to your doctor's appointment with you. Be sure to ask your doctor what you can do to prevent another seizure and what to do if you have another seizure.
Current as of:
October 19, 2020
Author: Healthwise StaffMedical Review: William H. Blahd Jr. MD, FACEP - Emergency MedicineAdam Husney MD - Family MedicineKathleen Romito MD - Family Medicine
Current as of: October 19, 2020
Author: Healthwise Staff
Medical Review:William H. Blahd Jr. MD, FACEP - Emergency Medicine & Adam Husney MD - Family Medicine & Kathleen Romito MD - Family Medicine
To learn more about Healthwise, visit Healthwise.org.
© 1995-2021 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Feeling under the weather?
Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.
Get started learning more about your health!
Our Interactive Tools can help you make smart decisions for a healthier life. You'll find personal calculators and tools for health and fitness, lifestyle checkups, and pregnancy.