need your head examined
need (one's) head examined
To be do, say, or believe something that seems completely crazy, delusional, or stupid. You need your head examined if you don't think giant corporations are in control of our legislators! You spent $400 on a T-shirt? You need your head examined.
need your head examinedbe foolishly irresponsible.
The implication here is that the examination will reveal proof of insanity.
1992 Patrick McCabe The Butcher Boy Any man thinks this work is easy needs his head examined—you want to be tough to work here!