This syndrome (previously known as epilepsy with grand mal seizures on awakening) is a common genetic/idiopathic generalized epilepsy. Individuals have infrequent generalized tonic-clonic seizures from the second decade of life, typically provoked by sleep deprivation.
This syndrome is characterized by onset of generalized tonic-clonic seizures between the ages of 5 to 40 years (peak 11-23 years, 80% of cases have their first tonic-clonic in the second decade). Seizures may be frequent, with one fifth of cases having more than one seizure per month prior to treatment. Treatment is required for life. Sleep deprivation, fatigue and alcohol lower threshold for seizures. Antecedent and birth history is normal, although there are patients with a previous history of childhood absence epilepsy. Neurological examination and head size is normal. Development and cognition is typically normal.