The International League Against Epilepsy (ILAE) is proposing a new nomenclature, replacing the confusing term antiepileptic drugs (AEDs) with antiseizure medications (ASMs). This approach has been partly motivated by the emergence of new treatments with antiepileptogenic or, more precisely, disease-modifying effects. This implies an effect on the temporal course of the disease, even when treatment is discontinued. However, the terms ASM and disease-modifying are not mutually exclusive. In some cases, ASMs can have this property. however, demonstrating this disease-modifying effect, and hence the development of these molecules, remains complex and difficult. The disease-modifying effect of ASM seems to depend on its etiological or pathophysiological effect on the developing epileptic disease, but also on other characteristics: target on etiological or pathophysiological mechanisms of the disease, level of cerebral maturation, time after onset of an epileptogenic event, dosage and duration of treatment. The development of this new type of treatment requires a better definition of the target populations, a better understanding of the cascade of epileptogenic phenomena, and the definition of new diagnostic and prognostic markers for epilepsy.