"I've seen a number of people that I think would be diagnosed with NPD that have psychedelic experiences and come out more grandiose."
https://www.reddit.com/r/[...]cissism_and_psychedelics/

"And he was thrilled, saying he was going to remember the feeling, the mindset, the new philosophy on life that had been opened to him.
That lasted about a month after the trip, degrading slowly into the old pattern. The only explanation I have is that narcs love novelty as fuel. They are pathologically bored, and always looking for a new fix to alleviate the feeling of non-being that they usually buffer by using people as supply. But, alas, it wasn’t enough to destroy those pesky defense mechanisms that every narc is so comfortable with, or the nasty beliefs that everybody is a competitor."
https://www.quora.com/Wha[...]cissists-use-psychedelics

Il devrait en prendre plus, ses problèmes (et ceux qu'il cause autour de lui) seraient résolus d'une façon ou l'autre