> Some of the thoughts and emotions they block are scary

Building on this, if someone is scared of the 'psychedelic' part then there is also MDMA which too lifts 'filters' and makes the subject aware of those thoughts and emotions so they can be processed, but takes away the fear and anxiety.

MDMA is not classified as psychedelic and currently studied for treatment of PTSD (among other diagnoses).

Psychonauts found a way to combine those effects: candyflip (a combination of LSD and MDMA) or hippieflip (psilocybin and MDMA).