Elvanse (lisdexamfetamine) increases dopamine and norepinephrine levels in the brain. Stuttering (especially the developmental type) has been linked in some studies to excess dopamine in motor control regions such as the basal ganglia — particularly the putamen and striatum. When dopamine levels rise above normal, it can lead to hyperactivation of the motor control system, which may disrupt the flow of speech. Therefore, it can potentially worsen stuttering.