My dr actually prescribed namenda for the concentration/memory issues...I don't have alz. But it is a common thing with bipolar, that cognitive effects are there even during periods of stability. This is a question that came up to me several years ago and why I came to PC, to ask this type of question of my fellow bipolar people.
I do however have an ADD dx, and can take nothing for it because it triggers mania. wellbutrin, stimulants both...and strattera did nothing for the symptoms. I just make LOTS of lists if I have something that must get done.