(insert drug of choice here) madness
I'd forgotten about that one! In fact, there was no shortage of rumors flying about in those days. My favorite was that dropping acid would screw up your chromosomes and make you have deformed babies.
If they really had wanted to put a stop to drugs they should have hired the PR departments of the tobacco companies to do the propaganda. They were fighting a brilliant rear guard action against all those activists who were spreading all that stuff around about cigarettes causing cancer. Their rhetoric has since been recycled many times...