To understand what synthetic marijuana and Bath Salts are, and how they came to exist, you have to know what a “designer drug” is.
A designer drug is a synthetic (chemically made) version of an illegal drug that was slightly altered to avoid having it classified as illegal. It is essentially an experiment by a chemist done to create a new drug that can be sold legally (on the Internet or in stores), allowing dealers to make money without breaking the law.
As law enforcement catches up with new chemicals that are so created and makes them illegal, manufacturers devise altered versions to steer clear of the law. So the cycle repeats.
https://www.drugfreeworld.org/....drugfacts/synthetic.