I am a big fan of lithium. My shrink started me off on 900 mg straight Li. I had toxic symptoms the very next day and I could barely drive to work. (I really shoudn't have walked let alone driven)
I cut back to 300 mg and things settled down. I moved up another 300 mg of timed release every few weeks and am now at 1200 mg and feeling better than I ever have before. I have not had any weight gain and my energy is so much more even.
I do drink lots of water.

Drink lots of water if you are on lithium.
Living with cyclothymia is like driving a car with 4 flat tires. It takes tremendous effort to get any where. So many things are easier once the rollercoaster of cyclothymia levels off. I really don't miss the frantic highs and I am glad to be without the lows. I can feel happy or sad, angry or scared on lithium. I am more aware of my thoughts and feelings and can make much better choices now.
I feel less out of control.