Lab experiments with rats might be pointing is towards what we have to do to mitigate this at least somewhat. Experiments showed that rats in a healthy social environment are much less prone to opioid addiction than ones living in isolation or having lived in isolation. See https://en.m.wikipedia.org/wiki/Rat_Park. I finds it easy to imagine that the same is true to some degree for humans. I wouldn't be surprised if the effect was even stronger on humans. We are very social animals after all.
I'm pretty sure the person you're replying to was using the word "crazy" in reference to terrorists, specifically the ones of a suicide variety, not your garden variety person who ends up addicted to prescription drugs.
Especially in the US the opioid addiction epidemic is caused mostly by doctor.
Last year less than 1% of the population tried heroin or opium poppy. A bit more than 5% of the population tried opioids.
'Opioids' are the prototype solution to human pain.
Have you never had surgery, a massive fever, or a broken bone?
Morphine and its analogs are probably up there with HVAC, internal combustion engines, and carbohydrates with respect to human progress.
And doctor prescription is caused mainly by drug company.
I have a hard time imagining anything except a real monoculture of individuals would emerge from such a possibility.
How can you prevent crazy people?
I'm asking because I often wonder what price we're willing to pay to make to make the chances of killed by another person 0%. Is there anyway to acheive that without creating a police state with zero privacy and zero possibility of dissent? If we start editing people's genes so they aren't "crazy" who decides what the legalized normative behaviour is?