Caffeine is banned for athletes, even though it is otherwise a legal substance. Perhaps we ought to contextualise the use of other drugs in order to better helpt those with addictions.
That said, I'm not sure how useful regular heroin use would be in an office situation. The filing would degenerate into chaos. I think, in all honesty, I'm just a bit confused because it is a hundred metres between my desk and the boss's office.