[toyg]

You cannot realistically get one without the other. Treatment often cannot be cold turkey, which means the addict will have to keep consuming (and hence carrying and buying) for a period; if that's illegal, treatment is not going to work. And no, methadone is not the same.

Taking Sweden as control, for example, they spend loads on health services and treatment; but without decriminalisation, their numbers are still terrible.

[usrusr]

Sure you can. Restrict illegality to use/possession outside of a treatment program. There already are many things pharmacists are not allowed to sell without a doctor's prescription, including strong opoids.

You would probably not want this kind of prescription to be signable by just any MD though, but that's another story.