"He has competed his treatment and has left," his rep tells PEOPLE. And, adds another source, the actor is "in great spirits. He's feeling good and he's ready to move forward."
As for his Beacher's madhouse, his rep adds: "David is concentrating on his health and well being right now ... although David remains fully supportive and a huge fan of Beacher's Madhouse and the Roosevelt Hotel."
When he entered rehab, Courteney Cox, who separated from Arquette in October, told PEOPLE, "I really admire David and his choice to take charge and better his life. I love and support him."