Paroxysmal Kinesigenic Dystonia After Methylphenidate Administration

We report a patient who developed paroxysmal kinesigenic dystonia shortly after initiation of therapy with methylphenidate for presumed attention deficit-hyperactivity disorder. Attacks persisted long after methylphenidate was discontinued and responded completely to treatment with carbamazepine. Though it is possible that methylphenidate caused this syndrome in our patient, it is more likely that the stimulant triggered the onset of a genetically determined disorder.