I’m anticipating a trip to hyperspace soon via Changa Airways, although I take anti-depressants (an SNRI called Desvenlafaxine). Will it be a safe return flight or will there be turbulence?

From what I have read your experience will be dulled if you are still on SSRI's. Also it is dangerous with MAOI's in Caapi and can lead to serotonin syndrome. It is best to taper off first if possible and have them out of your system foe at least a week. Do this supervised by GP. I am not a medico and this is only from what I have read. I have tapered off to experience. Take it slowly or you could go ratty.

Do not take any form of harmalas, syrian rue, caapi etc. while you are on ssri's or any anti depressants. You need to wait at least a few weeks minimum after ceasing use of these antidepressant type compounds before even thinking about taking harmalas.