Grand mal seizures, commonly known as Generalized tonic-clonic seizures, are seizures in which the muscles stiffen, rapid and jerky movements occur, and a person loses consciousness. Those who experience grand mal seizures do not remember them. This is the kind of seizure people typically picture when they hear the word “seizure”. They can occur in both children and adults, and last from 1 to 3 minutes.
Grand mal seizures have two phases: the tonic phase and the clonic phase. In the tonic phase a person will lose consciousness and the muscles will tighten, causing the person to fall. In the clonic phase the muscles will continuously flex and relax for about two minutes. Risk factors for grand mal seizures may include a family history of seizures, heavy alcohol use, heavy use of illegal drugs, brain injuries, infections, stroke, and lack of sleep.
The exact cause of grand mal seizures is unknown. Seizures are a result of abnormal electrical activity in the brain. In a grand mal seizure the entire surface of the brain is experiencing abnormal electrical activity. Doctors diagnose seizures by running a test called electroencephalogram (EEG). This test checks the brain for unusual electrical activity. Grand mal seizures generally occur only once. If they occur more than once, anti-seizure medications are used for treatment. Talk with your doctor to decide which treatment plan is best for you. Support groups are also good resources for support and information.