I take 1125 of Lithium. It was the only thing to control my mania early on.
I already had chronic kidney issues so I do all the right things for me: 2-4L of fluids/day, monthly blood tests (both of renal function and lithium level). My lithium level has been 0.8 for over a year.
My thyroid is not happy but my mum and grandma both had hypothyroidism by the time they were my age so it’s more likely to be hereditary as opposed to caused by lithium.