I am BP1, but have hit clinical depression. I think they put me on a AD because of this and I'm pregnant and they don't want to put me on too high of a dose of Lamictal. Lamictal, I've been on it on and off for a couple yrs. It never really helped much with depression for me. So maybe all I needed all along was a AD. I've taken as high of a dose as 400mg of lamictal when not pregnant. It helps with the mania for short periods of time, but then I always have to up my dose.
lexapro/cipralex/escitalopram I took it until yesterday for 2 months. it's very good but I had to stop it as I wasn't on an MS like you. True it works fast. In different forums people either take it or its cousin cipram/celexa/citalopram incidentally same danis company. Or wellbutrin too is well tolerated by BP pts. Of course don't exceed dose otherwise will bring mania but i assume not for you as you take lamictal.
However a point of concern why you take an AD as you take lamictal already which takes care already of the depression unless you are strongly BP2.
in my view this is one of the best AD's in the market as agreed by bipolar pts.