Of course. Obviously it depends on the person; who are they, what are they trying to achieve, previous experience etc. But in the more general sense, and in my opinion, I don't see the value of repeated use of psychedelics.. you get diminishing returns vs increased risk of harm - once you get the message, hang up the phone. I really do think they only need be experienced a handful of times at most, just enough to give a point of comparison and get a person thinking, and that relying on them as a crutch under the guise of 'spiritual' or 'medicine' is detrimental to the health of the individual.

I'm not anti-psychedelics, but I do have a lot of reservations about the culture surrounding them.