Selection of antiseizure medications for first add-on use: A consensus paper

•We defined by consensus criteria for selecting an antiseizure medication (ASM) for first add-on use.•Key criteria identified include efficacy, adverse effects, drug interactions, mechanism of action, and ease of use.•Among key factors, interaction potential and mode of action are especially relevant to add-on use.•The need to optimize adherence and to tailor drug selection to individual characteristics was emphasized.