Originally Posted by
Abundance 
Are these types of medicines able to be used on as "as needed basis"?
Yes, they are. In fact I try to only take it during the week because I develop tolerance to it quickly. Therefore, by body gets a break from it and when Monday comes i'm ready. It actually makes me look forward to Mondays b/c I know i'll be getting a lot done. I look forward to the creative surge and the excellent focus ability. It seems i'm much more interested in everything when I take it.