Opiates: Opioid Receptors
Cannabis: Cannabinoid Receptors
DXM: ???
The drug has a relatively "complex" relationship with the brain, from what I understand; if complex is a more preferable word, go with that. When I say that it is dirty, what I mean is: the way in which it interacts with the human brain is "dirty". Although I enjoy DXM, I don't believe it is "meant" for human consumption. I can feel the damage it does to me. Of all the drugs I've done in my life, I'm convinced that DXM has caused the most damage. LSD is basically harmless. Psilocybin is worse. Ecstasy is worse then psilocybin. Speed is worse than ecstasy. DXM is worse than speed. The cognitive after effects of prolonged DXM use are substantially greater than any other drug. If you take H every day, you'll be fine. If you eat weed every day, you'll be fine. If you take LSD every day, you'll be fine. The same cannot be said for DXM. I am afraid of consuming it more than once a week, though sometimes I do, because I know how much damage it does to me. Regardless of whether studies have definitively proved it. Just like how people noticed the correlation between smoking and death, before the term cancer was invented. The amount of damage DXM does to me, it is hard to justify using it at all.
I don't believe that heroin is particularly neurotoxic. And, yes, DXM feels dirty as fuck. It has a lot of physical side-effects. The body load is substantial. It makes your thoughts erratic and unorganized. Heroin is clean and clear. Heroin is, in my opinion, one of the cleanest drugs there is. To the uninitiated, a nodding junky might look like confused or even disoriented. Not so. The mindset is totally pure. Alcohol is dirty. DXM is dirty. Heroin is clean. Certain drugs have developed a symbiosis with humans, due to continual use throughout history. The natural drugs. The ones we are "meant" to consume.
All this research chemical shit, it's dangerous territory. Although DXM has existed recreationally for some decades, it is too "new", for me to consider it remotely safe. The only drugs I feel comfortable consuming, and guilt-free, are those that have been used traditionally throughout history. I believe natural opiates and natural psychedelics exist primarily to be consumed by animals. The drugs are designed for us by God.
No offence to Shulgin, but he ain't God. Maybe they'll get to the point eventually where drugs can be tailor made with minimal risk, but - currently - we're basically just experimenting. And the drug users. The people who take 2CB and DOI and DXM. They're guinea pigs. They're volunteers. They are test subjects... and the results, of said tests, are pending.