Tonic-clonic seizures

Tonic-clonic seizures, formerly known as grand mal seizures, can affect both children and adults and are convulsive, caused by abnormal electrical activity in the brain. A single episode can occur or will repeat over time and become chronic. Epilepsy is the most common cause of tonic-clonic seizures.

As its name suggests, there are two phases of a tonic-clonic seizure. The first and shortest phase, or tonic seizure, causes a violent contraction of muscles accompanied by a loss of consciousness. The jaw also becomes clenched which may result in the tongue being bitten. The person may appear to be blue and because of air forced past the vocal chords, the patient may let out cries or moans. This phase usually will not last longer than a minute.

In the next phase, or clonic seizure, an intense jerking of muscles will begin, contracting and relaxing, until the spasms gradually subside at which time the person sighs then resumes a regular breathing pattern. This phase rarely lasts longer than a few minutes and is often followed by a period of confusion and exhaustion.

Treatments for tonic-clonic seizures typically involve medication, but vary depending on individual diagnosis and symptoms.

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