Dr Alex Karev At UCLA Medical Center

TMZ has learned actor Justin Chambers, Dr. Alex Karev on "Grey's Anatomy," checked himself in to the psych ward at UCLA Medical Center this week. Yes, it's the same place...

His rep confirmed to TMZ Chambers checked in on Monday and checked out yesterday.

The rep claims Chambers, a married father of five, was "exhausted and suffers from a sleeping disorder. He went in voluntarily to get some help."