Buproprion (Wellbutrin) has been effective in treating ADHD in some children who have not responded to other medications. It is important to monitor the dosage carefully, as there is an increased risk of seizure when more than 150 mg /dose or 450 mg/day are used in adults.
Monoamine Oxidase Inhibitors are rarely used to treat ADHD. They require a diet to control intake of tyramine which most children and many adults will not tolerate ( who wants to give up pepperoni pizza?). Controlled studies have shown these medications to be beneficial, however, when other medications have been ineffective.
For additional information, see:
Spencer, Thomas, et. al., Pharmacotherapy of Attention-Deficit Hyperactivity Disorder across the Life Cycle, J.Am. Acad. Child Adolesc. Psychiatry, 35:4, April 1996