I think it came on gradually but i am not sure tbh.
Every time I have an episode I have very fast onset.
My onset was slow. I count my first mental illness from when I was fifteen. I wasn’t diagnosed sz until I was about 30. I was pretty crazy when I was fifteen, but I was good at concealing it. I’ve always revealed a lot less of myself than there really was.
Mine started insidiously over a few weeks without me knowing what is was all about, then it escalated violently 5 years ago. Ever since I learnt to adjust to its recurring patterns.
I had mental health problems since I was 13 - anxiety attacks, as well as the beginning of voices, so I guess my sz came on gradually. When I was 18, though, I deteriorated suddenly and was in hospital a month after my breakdown, and was diagnosed two months after that.
My onset was very sudden at 46 (a little over a year ago). I had a few days of feeling kind of disconnected and strange and then I had a full blown psychotic episode which landed me in a involuntary unit. I have had 2 other episodes since then where I was hospitalized voluntarily. I went from perfectly normal to very ill in a snap. I was originally diagnosed with Bipolar with Psychotic features and it has since changed to Schizophrenia.