need (one's) head examined

To 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 examined

be 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!

need, want, etc. your ˈhead examined

(informal) used for saying that somebody is behaving in a crazy or stupid way: She spent $300 on a pair of shoes? She needs her head examined.