TRAINSPOTTING is a MUST SEE if you are going to have a serious discussion about movie drug use.
Also, if you EALLY dig into old titles, there was amovie that Richard Pryor did back in the early 70's...."Wild in the Streets"....anyway, the premise was TOTALLY bizarre!! It involves a music group that literally gets so popular, they get everyone hooked on som etype of LSD and introduce it into the Washington DC water system, so tha the countries laws get re-written by a bunch of "tripping" politicians...I remember watching this at a High School party where many of the viewers themselves were on acid (except for me and a few others)