I've never done drugs or even tobacco, but Steve Jobs claimed dropping acid changes your perspective on reality and was a big factor in his success. That gives me pause.
Will you realize some hidden truth about the nature of the universe? Most probably not. Will it teach you something about yourself and your mind? Most definitely yes.
Can this change you forever? Of course it can, and many it will. Can this trigger any dormant mental disease? Absolutely. Any profoundly shocking experience can, even binge drinking - met one person who ended up on lifelong schizophrenia treatment because of alcohol.
This always seems like such a strange rhetoric to me. If a drug "triggers" a "dormant disease" that you wouldn't have gotten if you hadn't taken the drug, why not just say the drug caused the disease?
During one of few mushroom experiences I encountered, i was lying in the bed, alone, eyes closed. I gradually lost all the sensory inputs from whole body, perceiving via some sort of 'inner vision'. I got dissolved into white mist of atoms and just swirled around in an endless dance to the tune of some relaxing music playing in real world.
When coming down, I literally slowly assembled myself back to original me, atom by atom, first the mind, then rediscovery of body, eyes, taste and so on. I felt very strongly that if something was broken in me, this assembly back wouldn't work very well, or at least it would reveal some dark spots in my personality. Maybe not trigger them, who knows.
I could break the experience anytime if I wanted, but there was no need, it was beautiful all the way through.