Exactly, it’s the strong psychological effects that make it more prone to the “bad trip” phenomenon. It’s unique to LSD.

While set and setting have something to do with it, these terms were invented specifically for LSD to help understand the “bad trip” phenomenon specific to LSD. Mescaline was studied far longer than LSD ever was, and it wasn’t until LSD became popular that the “bad trip” term became part of our vocabulary.

Many will tell you that mescaline, while similar to LSD in many ways, is far friendlier that LSD. Hence, there was no need for the term “bad trip” until LSD hit the scene and replaced mescaline use virtually overnight. Suddenly “bad trips” were popping up all over.

I’ve read lots of work on the Native American use of peyote and “bad trips” are virtually unheard of among members of the NAC.