Well, I know that my hallucinations started when I was 5 or 6, and I remember clear as day, I was actually seeing things that weren't there. It wasn't my imagination or an imaginary friend. I don't know if I would've been diagnosed schizophrenic (as you have to meet TWO Criterion A symptoms, and I couldn't be diagnosed with "delusions" as all the "crazy" thoughts were normal for a child of my age), but would antipsychotics have helped me then? Who knows.