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    Tonic-Clonic Seizures, Once Called Grand Mal

    |7 min read
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    Dovy Paukstys

    Founder, Komori Care

    Abstract photograph for the Tonic-Clonic Seizures, Once Called Grand Mal explainer
    Photo by Lorem Picsum on Unsplash

    Tonic-Clonic Seizures, Once Called Grand Mal

    A tonic-clonic seizure is the stiffen-then-jerk pattern most people picture. The older name was grand mal.

    Important: This article is educational and is not medical advice. It does not diagnose, treat, prevent, or cure any condition. Komori is not a medical device, is not FDA-cleared, does not detect seizures, and is not intended for people with epilepsy. Talk with a neurologist or epileptologist about personal medical decisions. Households living with epilepsy should use clinically validated seizure-detection devices as directed by their care team.

    What the name describes

    Tonic means muscles stiffen. Clonic means they jerk in a rhythm. A tonic-clonic seizure is those two phases in sequence, with loss of awareness.

    ILAE kept tonic-clonic as the official term in 2017 and dropped grand mal from the classification. The old phrase will stay in conversation. If you use it with a clinician, they will know what you mean. The newer name is more precise, because not every big motor seizure is this pattern, and not every tonic-clonic seizure starts the same way.

    CDC groups tonic-clonic seizures under generalized motor seizures when they begin on both sides of the brain. The same motor pattern can also follow a focal start. That second path has its own name, focal to bilateral tonic-clonic.

    What bystanders usually see

    The tonic phase comes first. Muscles stiffen. Air forced past the vocal cords can make a cry or groan. The person loses awareness and falls if they are standing. The tongue or cheek may be bitten, so saliva can look bloody.

    Then the clonic phase. Arms and often legs jerk rhythmically, bending and relaxing at the elbows, hips, and knees. The face may look dusky if breathing is labored. As the body relaxes, the person may lose bladder or bowel control.

    CDC says these seizures usually last a few minutes and may leave confusion and tiredness afterward. Awareness returns slowly. The after-period is called the postictal state. Sleepiness, headache, sore muscles, and irritability are common. Some people have a temporary weakness on one side, called Todd's paralysis. NINDS says that weakness can last from 30 minutes to 36 hours and can be mistaken for a stroke.

    The person is not aware during the convulsion. What looks painful to watch is not something they can process in the moment. Pain, if it comes, tends to come after, from a bitten tongue, a fall, or muscle strain.

    Two ways this seizure can start

    A generalized-onset tonic-clonic seizure engages both hemispheres from the beginning. There may be no warning, or only a vague sense that something is about to happen. ILAE notes that a brief head turn does not automatically make the onset focal. Biology is not perfectly synchronized.

    A focal to bilateral tonic-clonic seizure starts in one network and then spreads. The person may have an aura first: a smell, a rising stomach feeling, deja vu, or a brief focal movement. Then the same stiffen-and-jerk sequence takes over.

    From the floor, those two can look identical. The history before the fall, and later EEG or imaging, is what separates them. That distinction matters for medicine choice and for surgery evaluation. It does not change the first-aid steps.

    NINDS still uses the older phrase secondary generalized for the spread pattern. ILAE replaced that phrase in 2017. You may hear both.

    What it is not

    Fainting can include a few jerks after the person slumps. Those movements are usually shorter and less intense than a tonic-clonic seizure. Pallor and a lightheaded warning are more typical of syncope.

    Psychogenic nonepileptic seizures can look convulsive. They are not driven by the same electrical pattern. NINDS says they do not respond to antiseizure medicine and need a different evaluation. Video-EEG is often how clinicians tell the events apart.

    A first convulsion always deserves medical review. Do not assume the label from a single home video.

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    First aid for this seizure type

    Use Stay, Safe, Side.

    Ease the person down. Cushion the head. Turn them on one side with the mouth toward the ground. Clear the space. Take off glasses. Loosen the neck. Time the seizure. Stay until they are fully alert.

    Do not restrain. Do not put anything in the mouth. Do not give mouth-to-mouth during the seizure. Do not offer water until they are fully awake.

    Call 911 if the seizure lasts more than 5 minutes, if another starts before recovery, if breathing or waking is a problem, if there is injury, if it happens in water, if this is a first seizure, if the person is pregnant, or if the person has diabetes and loses consciousness.

    NINDS and CDC both treat a convulsive seizure lasting over 5 minutes, or repeating without recovery, as status epilepticus. That is a medical emergency.

    Risk that belongs in the conversation with a clinician

    Tonic-clonic seizures are one of the seizure types most often discussed in sudden unexpected death in epilepsy, or SUDEP. CDC defines SUDEP as death in a person with epilepsy that is not caused by injury, drowning, status epilepticus, or another known cause.

    CDC estimates that for every 1,000 U.S. adults with epilepsy, one may die from SUDEP each year. For every 4,500 children 17 or younger with epilepsy, one may die from SUDEP each year. Most SUDEP deaths occur with a generalized seizure during sleep. The main risk factors CDC lists are generalized seizures and uncontrolled or frequent seizures.

    CDC's first recommendation is to take seizure medicine as prescribed and to talk with a clinician if seizures continue. Training other adults in the house in seizure first aid is on that same list. This article is not a device recommendation. Households living with epilepsy should use clinically validated seizure-detection devices as directed by their care team.

    After the seizure

    Help the person into a safe sitting or lying position. Tell them what happened when they can take it in. They may need to change clothes. They may want to sleep. They should not drive, swim, or climb until a clinician has said it is safe.

    If this was a first tonic-clonic seizure, it needs a prompt medical workup. If it happened in someone already under epilepsy care, the useful details for the next visit are duration, any warning, injuries, and how long the postictal period lasted.

    FAQ

    Is grand mal the same as tonic-clonic?

    It is the older popular name for the same stiffen-then-jerk pattern. ILAE now uses tonic-clonic, and then specifies whether onset was generalized, focal then bilateral, or unknown.

    How long do tonic-clonic seizures usually last?

    CDC says they usually last a few minutes. Call 911 if the seizure lasts more than 5 minutes or if another starts before the person recovers.

    Why does the person cry out at the start?

    Air is forced past the vocal cords as the chest and throat muscles stiffen. It is a mechanical sound, not a sign that the person is in pain or aware.

    Should I hold the person still so they do not hurt themselves?

    No. CDC says holding someone down can injure both of you. Clear the space and cushion the head instead.

    Can a tonic-clonic seizure start on one side of the brain?

    Yes. That is a focal to bilateral tonic-clonic seizure. First aid is the same. The distinction matters later, in the clinic.

    What is the postictal period?

    The recovery window after the seizure. Confusion, sleepiness, headache, and sore muscles are common. Some people have temporary one-sided weakness, Todd's paralysis, which NINDS says can last from 30 minutes to 36 hours.

    Sources

    Related

    • types-of-seizures
    • seizure-first-aid
    • status-epilepticus

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