I did a lot of both in my youth and have to affirm what Nan said. After a while, it was no longer possible to tell if I were high on marijuana, but only that I was not high. It took a long time to get it out of my system. One of the problems of alcohol usage my most American Indian tribes was that they had no cultural norms to place limits on the behavior, hence a high incidence of alcoholism among them. On the other hand, Judaism has many norms about the use of alcohol that limit its use as an intoxicant. Jews have a low incidence of alcoholism. Certainly the America I grew up in was much closer to the American Indians when it came to using marijuana. I see fewer restraints on the use of alcohol. I think of a beer commercial in which drinkers were in a hospital giving beer to everyone there, including surgeons in an operating theater. I am not aware of any development of norms that limit the intoxication with marijuana.
The issue of medical usage is a separate matter. We routinely allow the use of intoxicants to bring about some desired effect. Think of all the medicines that warn against driving until you know how they affect you. I recently was put on diltiazem for an irregular heart beat. It works quite well, but left me in a zombie-like state. The dosage was changed, so that I can now function again. If I were to drive in that zombie-like state and be involved in an accident, I would have been charged with driving while impaired, just as if I were drinking, or for that matter, using marijuana.
In sum, if we take up Jesus’ cross, then everything we do is judged as either glorifying or tearing down His name. Thus the question then becomes, can you build up the body of Christ while stoned? For myself, the answer was no. I do not see anything in American culture that would make me think it would be otherwise, either.