Jon Hamm admits 'Mad Men' has taken an "emotional toll" on him.
The 44-year-old actor recently completed a 30-day stint in rehab for alcohol addiction and though he hasn't blamed the show - in which he plays troubled ad agency boss Don Draper - for his struggles, he has found his job "challenging".
He said: "Don is a difficult headspace to be in for a long time.
"Acting is not physically demanding necessarily, but it takes an emotional toll, especially when you're playing a person who has a lot of emotions. You can have some sad days at work."
And Jon - who is in a relationship with Jennifer Westfeldt - admits it has been hard having to put his ordinary life on hold while working on the popular show, which recently wrapped filming and comes to an on-screen end in the coming months after seven seasons.
He told the UK's Grazia magazine: "You are away from your family, your friends, away from your life.
"Doctors appointments get pushed aside, life gets pushed aside because you're working from 6am until 10 at night. Every day. It's challenging."