Ethosuximide is used mainly in the treatment of petit mal epilepsy. However, it is also useful in akinetic and myoclonic attacks associated with generalised EEG spike-and-wave paroxysms.
Occasionally it is necessary to use a combination of sodium valproate and ethosuximide to control complex absences. This combination may also be used in patients with combined absence and tonic-clonic seizures where valproate may fail to satisfactorily control the absences.
The peak serum levels of ethosuximide occur 1-4 hours after administration and the control of absence seizures is highly correlated with plasma levels.
The summary of product characteristics should be consulted before prescribing this drug.