Are generic drugs really inferior medicines?

In this issue Gagne et al. report an elegant case-crossover study of seizures in patients on antiepileptic drugs. They found that a dispensation episode approximately triples the risk of having a seizure within 21 days, but the risk is not statistically different whether the dispensation was of the same brand-name or generic drug as previously used or a switch from brand-name to a generic or from a generic to a brand name. The cause of the seizure might be a delay in taking medication or late redispensation, among others, but apparently the nature of the product dispensed is not relevant in this study; this may alleviate some of the concerns about generic drugs and epilepsy.