Up until I was twenty two, I did pretty much every drug that I could get my hands on, with the exception of the various tranquilizers people take and some of the harder to get hallucinogens. I'm 28 now, maintain an A- average in school, and I think I get along pretty normally. I still smoke pot recreationally - I can't afford it, really, so I don't do it that often - and I find that I do just fine. I consume A LOT of alcohol on the playa, have coffee in the mornings at Coffee and Tea (they're truly a saintly people), and for the most part, have had a very hard time finding drugs there. My first year, someone offered me some E but I hadn't taken it before and wanted my first time to be with my then girlfriend. For the most part, though, other than some mushrooms, the pill I was offered, a bottle of homemade absynthe, and some pot (pretty rarely, oddly) I've almost never seen drugs on the Playa.
Coffee, I've heard, has mental health benefits, too, so I drink it but also fairly casually. I've tapered back from a pot a day (when I was in Reno) to about...I don't know...two pots a week. I've never gotten a withdrawal headache or anything. I do smoke cigarettes, though, which as far as I'm concerned is the most insidious drug available. I managed to quit a pretty serious meth addiction cold turkey when I was twenty-two and never touched it again. Nicotine...shit. I've tried to quit ten, fifteen times and never been successful. Concerning drug effects on the body and psyche...I think it has everything to do with one's personal physiology.
Thanks to Addis, I had more free time.