Hi there. That is def. a common side affect from most of the ADHD/ADD medications. Adderall does that to me, the thing to do it eat before taking the pill and that way all day long you still have the urge to eat. There isnt any vitamins that I can think of to stimulate her appetite, although there are things she can do to put on weight. From personal experience I would suggest def. having her eat right before and then making it a concious effort to eat about three times a day at least nutri grain bars. Some proteins. Protein bars are def. a way to go. If worse comes to worse try her on concerta. I did not experience any eating problems/lose of weight with that. Good luck my friend and don't hesitate to ask me any questions.

Brooke