When should antiepileptic drugs be started after a first seizure?

The recommendation to initiate antiepileptic drugs after a first seizure is often contingent upon the presence of certain predisposing risk factors. These factors may include a strong family history of epilepsy, abnormalities identified on an electroencephalogram (EEG), or structural abnormalities revealed through neuroimaging, such as MRI. Starting medication in a patient with a single seizure is not typical without these considerations because the risk of recurrence is relatively low for many individuals.

In cases where there are predisposing risk factors, there is an increased risk that the individual may experience further seizures, hence justifying the initiation of treatment in these scenarios. Conversely, in the absence of mitigating factors, the decision to start antiepileptic drugs may be delayed until after a second seizure occurs, as the first seizure alone does not confirm a diagnosis of epilepsy. Therefore, this approach balances the need for effective treatment while also avoiding unnecessary exposure to the side effects of medication when the risk of recurrence is not significantly elevated.