Requirements for generic antiepileptic medicines: a clinical perspective.

Many antiepileptic drugs (AEDs) are now available as a generic product. This can potentially save the healthcare providers massive costs. Hence, governmental authorities have introduced rules and incentives for clinicians to switch from the original branded AED to a generic product. Clinicians and patients with epilepsy are reluctant to switch. The licensing of generic AEDs is based on the equation that bioavailability means therapeutic equivalence. However, from a clinical standpoint one has to consider several other relevant issues: (1) Do generic AEDs have the same efficacy, safety and quality? (2) Can generic AEDs be used as substitutions for brand AEDs? (3) Can generic products of AEDs be used interchangeably? (4) Does the generic AED manufacturer guarantee the long-term consistency of availability on the market? (4) Do generic AEDs reduce the costs, and--if so--are these costs worth any additional risk to patient's safety? This article reviews the clinical issues related to current bioequivalence, prescribability, and switchability of AEDs.