What are you using it for? If you are using it for other
problems other than ADHD, I suggest this 2 articles for you.
http://warner.blogs.nytimes.com/2009/04/23/the-side-effects-of-smart-drugs/?ref=opinion
http://www.newyorker.com/reporting/2009/04/27/090427fa_fact_talbot?currentPage=all
Just for perusal.