Drug misuse is not a disease, it is a decision, like the decision to step out in front of a moving car. You would call that not a disease but an error of judgment.
The basic tool for the manipulation of reality is the manipulation of words. If you can control the meaning of words, you can control the people who must use the words.
Science fiction writers, I am sorry to say, really do not know anything. We can't talk about science, because our knowledge of it is limited and unofficial, and usually our fiction is dreadful.
Reality is that which, when you stop believing in it, doesn't go away.