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What is a Generalized Tonic-Clonic Seizure?

Laura A.
Laura A.

A generalized tonic-clonic seizure is a common type of seizure involving every area of the brain. There are two stages involved in this type of seizure. The tonic phase, when the body becomes rigid, is followed by the clonic phase during which the more dramatic effects of the seizure take place. Convulsions and loss of control over bodily functions may happen in the clonic phase. A generalized tonic-clonic seizure can be caused by brain injury, illness, drug use or other medical conditions that change electrical activity in the brain. Anyone who witnesses this type of seizure should try to place the victim in a safe position to minimize damage.

A seizure is a medical emergency caused by abnormal electrical activities in the brain. People experiencing seizures lose control over their bodily functions. A generalized tonic-clonic seizure, also known as a grand mal seizure, is the most common type of seizure. People who suffer from epilepsy are particularly prone to this type of seizure, although a generalized tonic-clonic seizure also can result from a severe blood glucose fluctuation, drug use or injury.

EEG tests may be ordered to diagnose and develop treatment plans for generalized tonic-clonic seizures.
EEG tests may be ordered to diagnose and develop treatment plans for generalized tonic-clonic seizures.

These seizures can happen without warning or they might be preceded by symptoms such as seeing flashes of light, a tingling sensation in the skin, or an unexpected rush of emotion. The tonic phase is the first part of a generalized tonic-clonic seizure. This phase normally lasts for approximately 20 seconds. During the tonic phase, the muscles contract and the body becomes rigid. The victim loses consciousness and might fall to the floor. In some cases, the person experiencing the seizure can have difficulty breathing.

During the tonic phase of a tonic-clonic seisure, a person may lose consciousness.
During the tonic phase of a tonic-clonic seisure, a person may lose consciousness.

The tonic phase is immediately followed by the clonic phase. This is when the muscles begin to relax and contract repeatedly and the victim often has convulsions. He might also bite his tongue or cheek. The victim loses control over his body and this sometimes leads to temporary incontinence. The clonic phase of a generalized tonic-clonic seizure usually lasts for a minute or two and is followed by feelings of exhaustion, weakness and confusion. Seizure victims normally have no recollection of what transpired.

Anyone who witnesses a generalized tonic-clonic seizure should try to place the victim in a safe position to minimize damage.
Anyone who witnesses a generalized tonic-clonic seizure should try to place the victim in a safe position to minimize damage.

Often emergency medical assistance is not able to arrive on the scene of a generalized tonic-clonic seizure before it ends because these seizures only last a few minutes. Onlookers can’t do much to stop the seizure but they can help minimize injury to the victim. The victim often fails to recall the details of the seizure so it’s important for any witnesses to take note of all that transpired and relay this information to the victim or his doctor to aid diagnosis and treatment. It’s also a good idea to lay the victim onto his side to avoid swallowing or inhaling vomit and to place a pillow or other soft object under the victim’s head to prevent head injury.

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    • EEG tests may be ordered to diagnose and develop treatment plans for generalized tonic-clonic seizures.
      By: Tobilander
      EEG tests may be ordered to diagnose and develop treatment plans for generalized tonic-clonic seizures.
    • During the tonic phase of a tonic-clonic seisure, a person may lose consciousness.
      By: Photographee.eu
      During the tonic phase of a tonic-clonic seisure, a person may lose consciousness.
    • Anyone who witnesses a generalized tonic-clonic seizure should try to place the victim in a safe position to minimize damage.
      By: Igor Normann
      Anyone who witnesses a generalized tonic-clonic seizure should try to place the victim in a safe position to minimize damage.
    • Using illicit drugs can increase an individual's risk of having a generalized tonic-clonic seizure.
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      Using illicit drugs can increase an individual's risk of having a generalized tonic-clonic seizure.
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