The retrospective pre-post observational study was conducted to evaluate the real-world evidence of efficacy and tolerability of generic levetiracetam (oral tablet) which was switched from original levetiracetam (oral tablet) in patients with epilepsy at the national hospital for neurology and neurosurgery in Thailand. Epilepsy patients who received generic substitution to original levetiracetam at the same dose and had stable conditions of seizure were only included. In the period of 6 months, the investigators assessed the change of seizure frequency, the incidence of hospitalization due to breakthrough seizure, the incidence of adverse events and the incidence of composite outcomes related to dosage adjustment of antiepileptic drugs.

Inclusion Criteria:

• Diagnosis of epilepsy for at least 6 months prior to generic levetiracetam substitution;
• Same dosage form and strength of generic substitution to original levetiracetam;
• Stable dose of original levetiracetam and stable seizure frequency prior to generic levetiracetam substitution;
• Stable dose of generic levetiracetam after generic levetiracetam substitution

Exclusion Criteria:

• Absence seizure with levetiracetam monotherapy;
• Original levetiracetam in dosage form of oral solution or intravenous solution prior to generic levetiracetam substitution;
• Poor compliance;
• Death or loss of follow up;
• Unavailable data for evaluation of outcomes

Any epileptic patients who received generic substitution to original levetiracetam from February 2016 to May 2018