Some do, don't they?
At least that's what I've heard, being a teetotaller myself :-P A good friend of mine who's a former user did describe using heroin as feeling like "being wrapped in a warm blanket" to me.
In fact heroin might be a very good example of the kind of drug Tasha is talking about. People take it to feel good and then it can fuck up your body royally and you end up having to take it so you don't experience the horrible withdrawals.
