The pathophysiology of absence seizures has been linked to oscillatory thalamic-cortical potentials, calcium currents, and the interaction of GABAergic neurons.
It seems clear that the pathophysiology of absence seizures differs from other epilepsies which may, in part, explain the unique efficacy of ethosuximide in this syndrome.
Diagnosis is made upon history of absence seizures during early childhood and the observation of ~3 Hz spike-and-wave discharges on an EEG.
The new classification of the epilepsy syndrome provides mandatory and exclusionary criteria, as well as some points that signs that should be considered as alerts [4]
A randomized controlled trial including 453 children showed that valproate and ethosuximide had similar absence-free rate after 16 weeks of treatment.
[5] In addition, a prospective cohort of CAE found that ethosuximide was associated with a better rate of complete remission (hazard ratio 2.5 (CI95:1.1-6.0) in a multivariate analysis .