Don't know for sure.
I heard that, and someone else added that it is not possible to get a pilot's license if one has a history of using that kind of drug.
I asked my airline captain 25 year-old son this question and he said that you cannot be an airline pilot if you are taking ADD type medication.
I just remembered on the CHL (Concealed Handgun Lic.) application, the question asks if one has been on such medication ("Yes"=No CHL)
Anybody who bought a handgun from a dealer remember if that question is on the yellow sheet?