Methsuximide is a succinimide anticonvulsant medication marketed as a racemate under the tradenames Petinutin and Celontin. Methsuximide its therapeutic efficacy is largely attributed to its active metabolite N-desmethylmethosuximide, which has a longer half-life and achieves higher plasma concentrations, making it central to the studies of epilepsy pharmacotherapy and metabolite-driven drug action.