I took lithium for 20 years and can offer the following anecdotal information, keeping in mind that, as someone has already mentioned, it's different for everyone. I'm also new to the forum and have no medical or pharmaceutical training whatsoever.

1. I slept for two weeks straight when I started lithium. I've heard that others had the same experience.

2. The involuntary hand tremors became, at times, ridiculously exaggerated. People sometimes thought that I was compulsively gesturing at them. I hated having to make excuses for the tremor and was self-conscious that the tremor made me appear nervous, frightened or guilty when I wasn't. The tremor can be at least somewhat suppressed by the beta blocker propranolol, which some musicians take for stage fright.

3. Prolonged lithium intake will eventually clog your kidneys and you'll have to stop taking it. A responsible prescribing physician will draw blood periodically to monitor your glomerular filtration rate, which measures your kidney function, and once your GFR crosses a certain threshold, you're done with lithium and must resort to an anticonvulsant or some other mood stabilizer. This happened to me a few years ago and I had to switch to Depakote after spectacularly unsuccessful trials of Lamictal, Tegretol, Carbamazepine and Effexor.