Absence seizures - these are typically frequent (multiple daily), brief (3-20 seconds) and awareness is severely impaired.
CAUTION Seizure duration >45 seconds, frequency less than daily or a post-ictal phase are not seen consider focal impaired awareness seizures, other epilepsy syndromes or non-epileptic staring.
CAUTION If awareness is not severely impaired childhood absence epilepsy is unlikely, other syndromes with absences should be considered.
Generalized tonic-clonic seizures - these rarely precede or occur during the active absence seizure period, they can be seen in adolescence in patients who evolve to have other idiopathic generalised epilepsy syndromes.