The primary purpose of this study is to investigate the effectiveness reflected by the retention rate of perampanel as the only add-on treatment in adult participants with primary generalized tonic-clonic (PGTC) or secondarily generalized tonic-clonic (SGTC) seizures based on focal or idiopathic generalized epilepsy in a non-interventional (observational) setting.

Inclusion Criteria:

1. Confirmed diagnosis of epilepsy with PGTC or SGTC seizures based on focal or idiopathic generalized epilepsy
2. Active epilepsy with GTC seizures, demonstrated by the occurrence of at least 1 GTC seizure within 3 months before inclusion
3. The decision to prescribe perampanel was made by the physician before and irrespective of his/her decision to include the participant in the study
4. Receiving treatment with perampanel in line with the current Fycompa (perampanel) SmPC
5. Perampanel must either be newly administered as the only add-on treatment to a current antiepileptic drug (AED) monotherapy or must be planned to substitute one of two AEDs of a current dual therapy planned to be stopped within 2 months after initiation of treatment with perampanel. It will be specified which AED is planned to be substituted by perampanel upon inclusion. It is assumed that participants start treatment with perampanel closely after the baseline visit. Retrospective inclusions will be allowed, but only if the time between the initiation of perampanel treatment and inclusion does not exceed 7 calendar days. In this case, the baseline visit documentation should reflect the situation (including seizure situation 3 months before baseline and baseline medication) to the date perampanel treatment was initiated

Exclusion Criteria:

1. Participants with known psychogenic non-epileptic seizures
2. The participant had already received perampanel in the past
3. Simultaneous participation in an interventional clinical study and/or taking an investigational drug

Participants with PGTC or SGTC seizures.

Eisai's data sharing commitment and further information on how to request data can be found on our website http://eisaiclinicaltrials.com/.