[rapind]

Make the substances and use of them legal to sell and use on one's self. However, make it illegal to market / advertise the substance since that is much easier to control just using fines instead of incarceration.

Attach stigma to it, like we have done with cigarettes (though not e-cigs...). The art / film / literary world will still try to make it sexy (rebellious) on occasion, but without full on marketing it's unlikely you'd see widespread use.

Possibly tax it, although I'm not 100% onboard with that, since it would eventually motivate government to lift the marketing restrictions.

For anything that's instantly addictive after one or two uses, perhaps it would be possible and worthwhile to try and create a diluted version that's safe for people to try it out without completely destroying their life.