Generic substitution for brand name antiepileptic drugs: A survey

Background/Objective: There are presently 26 different generic preparations for five brand name antiepileptic drugs (AEDs) on the Canadian market with others likely to be released in the near future. The purpose of this revie w is to examine the basis for the controversy surrounding generic substitut ion for brand name antiepileptic drugs, to present the results of a survey of neurologists' and patients' attitudes toward generic substitution and to increase neurologists' awareness of the issues. Methods: The current feder al and provincial regulations pertaining to generic drug approval and subst itution are reviewed. Published anecdotal and survey reports of the effecti veness and tolerability of generic substitution for AEDs are reviewed. A pi lot questionnaire survey of 83 patients from four adult epilepsy clinics an d 46 neurologists from across Canada was undertaken to determine attitudes toward generic substitution. Results and Conclusions: Several authors have suggested that some AEDs, particularly those with a narrow therapeutic inde x, may pose problems with generic substitution. Although generic AEDs are l ower in price, possible increased side effects and morbidity and the need f or closer monitoring could partially offset the cost savings. The results o f our survey highlight significant unawareness of the process of generic su bstitution among both patients and neurologists and reveal a general level of discomfort among neurologists to prescribe generic AEDs. Further data sh ould be obtained about the potential consequences of generic substitution i n epilepsy patients.