I'm looking for a word that gives the same meaning as advocate below, but with a negative twist:
He advocates not doing drugs.
I want to present this better, and emphasize that "He" stands behind (i.e. advocates) not doing drugs.
This sentence, for example, does not work:
He recommends not doing drugs.
Edit: To be clearer, ideally it would read as if he physically worked against it, like (I'd say) advocate implies.