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What Are Generalized Tonic-Clonic Seizures?

Generalized tonic-clonic seizures, or grand mal seizures, affect the whole body. They usually involve rigid muscles, severe muscle contractions, and loss of consciousness (fainting). People of any age can have them, as a single seizure or part of epilepsy.

What Causes Generalized Tonic-Clonic Seizures?

Abnormal activity of brain nerve cells occurring at the same time in many parts of the brain causes these seizures. Seizures may be brought on by head injuries, strokes, brain infections, very low blood sugar, and tumors. More than half the time, the cause is unknown.

What Are the Symptoms of Generalized Tonic-Clonic Seizures?

These seizures involve four phases. Often signs (auras) warn of a coming seizure. Auras include an odd feeling, strange taste or odor, and headache. Phase 2 (tonic phase) consists of rigid stiffening of the body for a minute or less, and fainting. The tonic-clonic phase (phase 3) appears as strong muscle contractions and relaxations and convulsions and can last several minutes. Loss of consciousness and loss of bladder and/or bowel control may occur. People may have trouble breathing or temporarily stop breathing. Just after a seizure is the postictal phase (phase 4). People slowly return to consciousness.

Lasting tonic-clonic seizures are an emergency called “status epilepticus.”

How Are Generalized Tonic-Clonic Seizures Diagnosed?

The health care provider will make a diagnosis from a medical history and physical examination. The health care provider will do electroencephalography (EEG), a test to check the electrical activity in the brain. Magnetic resonance imaging (MRI) or computed tomography (CT) will be done to get pictures of the brain. Blood tests will also be done to check for other causes of seizures. A doctor who specializes in disorders of the nervous system (neurologist) may be involved in your care.

How Are Generalized Tonic-Clonic Seizures Treated?

The main treatment is medicine. Sometimes more than one anticonvulsant drug may be used. The health care provider may get blood samples periodically to make sure that the correct dose is being used. Often, medicine will reduce the frequency and severity of seizures, but some people may continue to have them.

DOs and DON’Ts in Managing Generalized Tonic-Clonic Seizures:

  • DO take your medicine as prescribed to prevent seizures.
  • DO wear a medical alert bracelet stating that you have a seizure disorder and listing your medicines.
  • DO teach your family and friends about your disorder and what to do if you or someone else has a seizure. Prevent injuries by cushioning the head, turning the person on their side, and taking away items that could cause injuries. Don’t hold the person down or force anything into the mouth.
  • DO tell someone near you that you feel a seizure starting, and lie down.
  • DO call for medical help if someone is injured during a seizure, has trouble breathing, or doesn’t regain consciousness shortly after a seizure.
  • DO call 911 if someone has continuous tonic-clonic seizures. Status epilepticus is a medical emergency.
  • DO call your health care provider if you have any problems with your medicines.
  • DO call your health care provider if your seizures become more frequent or severe.
  • DON’T operate dangerous machinery or drive unless your health care provider approves.
  • DON’T swim alone.
  • DON’T climb on ladders or roofs in case you have a seizure.

Contact the following source:

  • Epilepsy Foundation of AmericaM
    Tel: (301) 459-3700
  • American Academy of Neurology

Copyright © 2016 by Saunders, an imprint of Elsevier, Inc.

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