my pdoc started me on 400mg and went up by 400mg every week, doing blood work weekly to find theraputic levels.
i was taking non-extended release tablets (camcolit) taken once daily around 10 pm with blood work usually at 10 am to get the peak level reading.

i used to take 1200 mg daily to be at a .6 /.7 level
i would take 1600 mg daily when in an episode to even out around .8
but everyones body cheimstry is different... some people are between .6 and .8 at just 600 mg!