If you're interested in studying the closest thing to it, look at the rise in popularity of Kratom, a Southeast Asian plant containing opioid alkaloids. It's commonly used by opiate addicts as a replacement therapy, and also by others as self-medication for anxiety, depression, and pain.

I'm not recommending anyone try it... nobody's entirely sure if it's safe, or if it could function as a gateway drug to harder opiates. But it's worth considering the good it may be doing for some people.