can confirm. Same with many of my friends. All heavy weed smokers, all used psychedelics. A worrying % went on to have some mental health issues.
Now I know all the pro-weed people say "yeah but it is those pre-disposed to having schizophrenic episodes". Perhaps, but at the sample rate in my experience and others who have met later on the % is far higher than I would have expected to be.
Same for just weed smoking. I post on a music forum, where near all members used to be heavy smokers . And anecdotally, about 80% had mental problems due to weed smoking. The cycle is clear. Heavy weed smoking for years. Stop enjoying it, but have become dependant. Come home from work. Smoke, freak out for an hour, effects wear off, smoke again, repeat. This goes on for 1-2 years before the realisation hits in, smoking is not good for me any more
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for the record all were also poly-drug users, not exclusively smokers, so it could be caused by other drugs or the combination of. But I have no doubt it saying, this is not only people pre-disposed to mental health issues