I don't really know how I would go about it, but I think the only solution is to make people not want to turn to the drugs in the first place.
Make poor people less poor? Make people feel better about their lives and prospects?
I guess I would spend a heap of money working out what makes people turn to the drugs and try and help them solve those problems some other way.
I think those are two unrelated issues. There's many places in the world where people have substantially less than in the US but have much higher life satisfaction and extremely lower rates of drug addiction.
There are rules for safe drug use. There are test kits (today, back then they were expensive) and most countries gladly have drug checking places as well.
The issue aren't the drugs but the culture and knowledge around it.
There is no "culture" here. It's just some kid getting a pill from a friend at school. They're not going to check it for safety.