Lexapro (U.S. name) = Cipralex (Canadian name) => contains escitalopram
http://forums.psychcentral.com/meds/lexapro.html

Celexa is something else entirely, it's the (older) sister drug of Lexapro.

Celexa (U.S. name) = Celexa (Canadian name too!) => contains citalopram
http://forums.psychcentral.com/meds/celexa.html

Best ask your doctor what drug he's switching you to.

I've heard that Celexa IS cheaper than Lexapro. It's a different dosing as far as I'm aware, on top of containing a slightly altered drug. Lexapro is more concentrated I think.

Celexa was created first, then Lexapro was created.