According to Mayo Clinic, a grand mal seizure is a type of bodily convulsion that is also known as a generalized tonic clonic seizure. This type of seizure is characterized by loss of consciousness and violent muscle contractions.
According to Mayo Clinic, a grand mal seizure is caused by abnormal activity in the brain. Most often, grand mal seizures are caused by epilepsy, but in some rare cases, they can occur due to low blood sugar, high fever or stroke. Many patients who experience grand mal seizures only have one throughout their lives; however, a small percentage of people with epilepsy may need anti-seizure medication daily to prevent more grand mal seizures from occurring.