Dr. Jackson, Teal'c and others in “Unfinished Business”

From what I've been able to translate so far with Loren's help, the Goa'uld used to use this place as some sort of, opium den. The only difference is their symbiotes must have kept the host's mind chemically balanced once they left.

Then it is most likely I will be able to leave this planet.

Oh how nice for you.