Psychedelic mushrooms. I always used to pick Schizophrenic as a starting trait when I was a nub.
I once had a character that ran into the forest, hurt as hell and starving, found a cabin and foraged mushrooms. Ate them. That, combined with the schizophrenic episodes… The hallucinations were many I tells ya.
Other than that I’d say cocaine or meth. Easy to find, gets you out of crappy situations quickly.