A generalized tonic-clonic seizure is a seizure involving the entire body. It is also called a grand mal seizure. The terms "seizure," convulsion," or "epilepsy" are most often associated with generalized tonic-clonic seizures.
For more information see:
Seizure - tonic-clonic; Seizure - grand mal; Grand mal seizure; Seizure - generalized
Causes, incidence, and risk factors
Generalized tonic-clonic seizures may occur in people of any age. They may occur once (single episode), or as part of a repeated, chronic condition (epilepsy).