Generalized Tonic-Clonic Seizures

What Is A Generalized Tonic-Clonic Seizure?

This type of seizure (also called a convulsion) is what most people think of when they hear the word “seizure.” An older term for this type of seizure is “grand mal.” As implied by the name, they combine the characteristics of tonic (stiffening) and clonic (jerking) seizures.

  • When people have tonic-clonic seizures, they are not aware of what’s happening.
  • This is a generalized seizure type, meaning it involves the entire brain.
  • The tonic phase comes first.
    • All the muscles stiffen.
    • Air being forced past the vocal cords causes a cry or groan.
    • The person loses consciousness and falls to the floor.
  • After the tonic phase comes the clonic phase.
    • The arms and usually the legs begin to jerk rapidly and rhythmically, stiffening and then relaxing at the elbows, hips, and knees.
    • After a few minutes, the jerking slows and stops.
  • During a tonic-clonic seizure, a person may bite their tongue or inside of their cheek. If this happens, saliva may look a pink or bloody.
  • The person’s face may look dusky or a bit blue if they are having trouble breathing or the seizure lasts too long.
  • The person may lose control of their bladder or bowel as the body relaxes.
  • Consciousness, or a person’s awareness, returns slowly after this type of seizure.
  • These seizures generally last 1 to 3 minutes. Afterward, the person may be sleepy, confused, irritable, sore and/or depressed.

Example of a Generalized Tonic-Clonic Seizures in a Person with LGS

(WARNING! Graphic Content)

Thank you to the families who shared these heartbreaking videos with us so we may educate others. An EEG is the only way to determine the exact seizure type. We did not have EEG for these video’s so thank you to the physicians, who, as a part of their daily practice, regularly review videos of their patients having seizures and have reviewed these videos to help us best determine the seizure type represented.

First aid:

Roll the person on their side so they don’t breathe any saliva or other secretions into their lungs (aspirate). This can lead to pneumonia. Make sure the person is breathing is okay, and ensure they don’t injure themselves. Time the seizure.

Emergency Care:

A seizure that lasts more than 5 minutes (status epilepticus), or three seizures in a row without a clear recovery between them (seizure cluster), is a medical emergency. Administer at-home seizure rescue medication immediately and if the seizure does not resolve, call for emergency help.

The information here is not intended to provide diagnosis, treatment, or medical advice and should not be considered a substitute for advice from a healthcare professional. Content provided is for informational purposes only. LGSF is not responsible for actions taken based on the information included on this webpage. Please consult with a physician or other healthcare professional regarding any medical or health-related diagnosis or treatment options.

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Updated February 10, 2022