The economic implications of generic substitution of antiepileptic drugs: a review of recent evidence

Expert Opin Pharmacother. 2009 Oct;10(14):2317-28. doi: 10.1517/14656560903140525.


Background: The US Food and Drug Administration (FDA) considers generic and branded drugs to be therapeutically equivalent if they are pharmaceutically equivalent and bioequivalent. The American Academy of Neurology (AAN) disagrees and opposes generic substitution of branded antiepileptic drugs (AEDs) without physician and patient approval due to the risk of loss of seizure control.

Objective: To review the evidence to date surrounding the economic impact of brand-to-generic substitutions of AEDs.

Methods: A systematic search of PubMed and MEDLINE was conducted; the bibliographies of key articles obtained from the search were used to identify additional sources.

Results/conclusion: Current literature suggests statistically higher overall healthcare costs during periods of generic AED use than during periods when branded AED are used, consistently demonstrated across different countries (Canada and the USA) and in both stable and unstable epilepsy patients, with more pronounced cost increases in patients receiving multiple generic versions. Brand-to-generic substitutions of AEDs do not necessarily reduce overall healthcare costs and may even increase them.

Publication types

  • Comparative Study
  • Review

MeSH terms

  • Anticonvulsants / economics*
  • Anticonvulsants / pharmacokinetics
  • Anticonvulsants / therapeutic use
  • Canada
  • Cost-Benefit Analysis
  • Drugs, Generic / economics*
  • Drugs, Generic / pharmacokinetics
  • Drugs, Generic / therapeutic use
  • Epilepsy / drug therapy
  • Epilepsy / economics*
  • Health Care Costs*
  • Humans
  • Therapeutic Equivalency
  • Treatment Outcome
  • United States


  • Anticonvulsants
  • Drugs, Generic