Consciousness will quickly be lost and the skeletal muscles will suddenly tense, often causing the extremities to be pulled towards the body or rigidly pushed away from it, which will cause the patient to fall if standing or sitting. There may also be upward deviation of the eyes with the mouth open. The tonic phase is usually the shortest part of the seizure, normally lasting only 10–20 seconds. The patient typically expresses brief vocalizations like a loud moan upon entering the tonic stage, due to air being forcefully expelled from the lungs. This vocalization is commonly referred to as an "ictal cry." Starting in the tonic phase, there may also be bluing of the skin from respiration impairment as well as pooling of saliva in the back of the throat. Increased blood pressure, pupillary size and heart rate (sympathetic response) may also be noted with clenching of the jaw possibly resulting in biting the tongue. The initial tonic phase may be preceded by repetitive rhythmic or arrhythmic jerks or by the absence seizure. Clonic phaseThe clonic phase is an evolution of the tonic phase and is caused by muscle relaxations superimposed on the tonic phase muscle contractions. This phase is longer than the tonic phase with the total ictal period usually lasting no longer than 1 min. Skeletal muscles will start to contract and relax rapidly, causing convulsions. These may range from exaggerated twitches of the limbs to violent shaking or vibrating of the stiffened extremities. The patient may roll and stretch as the seizure spreads.
Long-term therapy may include the use of antiepileptic drugs, surgical therapy, diet therapy (ketogenic diet), vagus nerve stimulation, or deep brain stimulation. Terminology
Generalized tonic–clonic seizures can have a focal onset (described above) that progresses into a generalized seizure or be a generalized seizure at the onset. The term "Grand Mal" is outdated and nonspecific, referring to generalized tonic-clonic seizures with either a focal or generalized onset. See also
Focal seizure
Absence seizure
Epileptic seizure
Non-epileptic seizure
Tonic (physiology)
Clonus
Postictal state
Electroencephalography

References
External links

Generalized tonic–clonic seizure at Curlie