[pjerem]

> if you're already prone to certain kinds of mental illness (you might not know it)

Though you can have some solid hints. First it's important to say we are talking about psychosis related illnesses.

First one is nobody had mental illness in your family. Second one is your age : most mental illness develop when you are a teenager or in your early twenties. If you are 30+, you can consider that LSD will not reveal anything hidden.

Though you still get the risk of bad trip, which you can manage with a good set & setting and not being alone if you prefer.