Isosafrole, a stiripentol analog, is a potent LDH inhibitor. Stiripentol is a new-generation antiepileptic drug, and its chemical structure is unrelated to other antiepileptic drugs. Seizures and epileptiform activity are reduced by inhibition of the metabolic pathway via lactate dehydrogenase (LDH), which is a component of the astrocyte-neuron lactate shuttle. Isosafrole is a substructure of stiripentol that lacks the hydroxyl group and tertiary-butyl group of stiripentol. Isosafrole strongly inhibited the pyruvate-to-lactate conversion by both LDH1 and LDH5, suggesting that it inhibits lactate production itself. Isosafrole suppresses seizures in vivo. Going by the lactate reduction by ketogenic diets, LDH inhibitors for the pyruvate-to-lactate conversion, such as isosafrole, would be more effective for antiepileptic actions. Isosafrole is a known inducer of some of the liver enzymes of the cytochrome P-450 group in rodents, especially CYP1A2.