generalized tonic-clonic seizure

pathology

Also known as: grand mal, tonic-clonic

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June 29, 2026

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A generalized tonic-clonic seizure, also known as a grand mal seizure, is a severe type of seizure characterized by an abrupt loss of consciousness. This is followed by a prolonged period of muscle stiffening (tonic phase), and then by rhythmic, jerking muscle spasms (clonic phase). These seizures can last for several minutes and may be accompanied by convulsions, biting of the tongue, and loss of bladder control. Following the seizure, the individual typically experiences confusion and sleepiness, with no memory of the event. Generalized tonic-clonic seizures can be a symptom of epilepsy or caused by other conditions such as brain injury or infection.123

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epilepsy
Generalized-onset seizures
…to by the older term grand mal, are commonly known as convulsions. A person undergoing a convulsion loses consciousness and falls to the ground. The fall is sometimes preceded by a shrill scream caused by forcible expiration of air as the respiratory and laryngeal muscles suddenly contract. After the fall,…
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…to by the older term grand mal, are commonly known as convulsions. A person undergoing a convulsion loses consciousness and falls to the ground. The fall is sometimes preceded by a shrill scream caused by forcible expiration of air as the respiratory and laryngeal muscles suddenly contract. After the fall,…
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nervous system disease
Generalized seizures
…type of generalized seizure is tonic-clonic seizures, in which an individual loses consciousness without warning, falls, and stiffens, because of muscle contractions. Rapid jerking of the entire body follows and ceases in approximately one minute. The person regains consciousness a few minutes later. Immediately afterward the individual is usually confused…
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…type of generalized seizure is tonic-clonic seizures, in which an individual loses consciousness without warning, falls, and stiffens, because of muscle contractions. Rapid jerking of the entire body follows and ceases in approximately one minute. The person regains consciousness a few minutes later. Immediately afterward the individual is usually confused…
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