Thanks everyone. I am thankful that my psychiatrist, who caught the lithium toxicity/kidney problem, is referring me to a specialist, even though the labs aren't showing anything notable (as far as I know). In the case of diabetes insipidus at least, I've read there are more specific tests that can be done. And maybe the labs look clean to someone who specializes in psychiatry, but would show something different to a nephrologist or an endocrinologist. If it IS diabetes insipidus, that's covered by an endocrinologist anyway, so when I see mine at the end of the month, I'll see what he says.

CaptainChaos79, they tested my liver function as well as my kidney function, and the liver came back ok, it was the kidneys that came back abnormal. I'm not really experiencing any gallbladder or liver symptoms, but am definitely experiencing kidney-related symptoms. I will look into gallbladder cleanses though. Also, my levels aren't coming back toxic any more. My psychiatrist cut the dose in half and my levels dropped. It's being lowered further today. In 2 weeks I should be off lithium entirely.