I had bloodwork a few months before starting Li, all was normal then.
Had more bloodwork in Dec when I was at 750mg, was still good Li was still too low. .5
So went up to 900 but wasn't stable enough, still cycling.
Went up to 1200mg, I don't know my exact serum level but my doc said it was not toxic.

Side effects I have had crazy thirst, urinating more(obviously) ravenous appetite, bloating, constipation, weight gain about 5 lbs while working hard to not, difficulty concentrating, forgetting words, feeling detached. Some other things that started are from my thyroid damage..my period stopped. Sorry if you are a guy.

It seemed to prolong my cycling ( I rapid cycle) but blunt the extremes. So I still had my episodes but they weren't as bad but lasted longer. Which still kinda stinks.

Hope this helps.