I don't smoke or take drugs. I would never try but it is also strictly forbidden for me. This is one of the reasons why I am not allowed to have and spend money without permission. I wouldn't even be able to buy cigarettes or drugs.
It is a little bit different with alcohol. In general it is forbidden, too but on some occasions I get the permission to drink responsible (this means not more then one drink any two hours). When I was younger I was drunken once but my father gave me a lesson I won't forget so I never tried it again. BTW: I didn't even liked the feeling.