One of the best is to listen to someone who's "been there" and then come back from the edge, like someone who does Narcotics Anonymous meetings and has worked the steps. (Not someone who just shows up to drink coffee and listen to the stories.)
What is a drug, anyway? Here's a good clue: there's an excellent book called "Chocolate to Morphine" that covers a lot of the subject.
Here's another clue: Sugar is a drug. It's habit forming. It's refined, far removed from its natural state. I don't call it a food; the very things removed from it in the refining process are things you need to use it in the body. And sugar, starches, and carbohydrates make you fat. Check out The Atkins Diet.
Opium, morphine, and heroin are all drugs in various stages of refinement. I had some morphine once but due to having three broken ribs I wasn't able to enjoy it. What I mainly know about these things, from people who have been there, is that once you get the monkey on your back, it's permanent. You can't dabble after that; you can't do just one.
Nicotine is a drug, and for purposes of discussion I'll say that it is "the" drug that's in tobacco. This is a good place to make a distinction: tobacco is not a drug, but it contains one (or more). (There are probably other substances that exacerbate the problems.) Now here's a monkey I can talk about with a little bit of authority. I've been there. When I was in high school I was smoking, and I kept at it for about ten years. I quit one morning, I suppose this is a bit unusual, but here's how it went: every day when I woke up I would do the sequence "alarm clock - light - cigarettes" before I even got out of bed. One day in December 1967 it was "alarm clock - light - cigarettes - trash" and I didn't smoke for two and a half years.
One evening I and some other guys were having a little ad-hoc party out on a back road, drinking beer and swapping stories, and I bummed a Marlboro. Just one. Ha. This would be 1970. In about 1989, after trying to quit for several years, I finally did it -- on Ash Wednesday. (What can I say about that? It worked.)
Just one. That's the point here, "just one", and almost twenty years later I got loose. Since quitting I dreamed about smoking exactly once -- and I didn't like it in the dream.
The next substance should probably be alcohol. These days it is generally recognized as being among the drugs. I'm happy to report that I don't have an alcohol problem. I had a beer the other day, and there's another one in the fridge to go along with my next knockwurst. Alcohol is actually a food to a small degree, and most so in beer. It's metabolized rather slowly, however, and since it's also a poison too, you can't really live on beer. For very long.
Drug Education these days does tend to include alcohol, as I suppose I implied in the previous paragraph. I don't know what kind of BS they include. I did notice something the other day when I was at the Department of Motor Vehicles office to check on efforts to clean up a mess that the experts at headquarters had made last year (see "hamplates"). This is paraphrased of course, but there was a sign up about how one beer can send you straight to hell. A few years ago I was in New Jersey for a couple of months, and was pleased to see a totally honest way of dealing with the subject in their driver's license manual. They said that one drink is likely to have little deleterious effect on your driving, and may in fact even improve it, by way of removing the tensions of the day. However, they went on to state, with further consumption, one's driving ability goes downhill quite rapidly. Such honesty is rare and refreshing these days, in or out of governmnet.
I mentioned poison above, and a word about that: everything is poison. I once asked a chemist something about poison, and that's what he said. And to clarify that, he added "If you don't believe it, eat a tablespoon of salt."
One thing I've left out is the inevitable discussion of marijuana/pot/grass/boo/parsley/etc. I didn't exhale. Click here.