It's worth a try. I was told to make sure I was eating a consistent amount of salt and after my first toxicity salt would definitely help. I had something called diabetes insipidus on lithium where my kidneys didn't hold on to electrolytes at all and flushed everything out to the point that when it was diagnosed I was actually peeing every 45 minutes without noticing until told to pay attention. My urine output was nearly double normal. So it is possible that was why salt helped me but the DI wasn't diagnosed for probably 2 years after my first toxicity and I am pretty sure salt (and ice water) helped even earlier than that.

I was able to take the entire dose at night. My doctor actually really encouraged this but obviously I wouldn't shift your dose without asking your own dr about that one. Extra salt isn't going to hurt you unless you start eating it by the jar or something but changing med times is a little different.

Hope you are able to find something that helps you feel better. If you don't soon you probably should get a level drawn just in case; nausea and GI issues are signs of toxicity and it can sneak up on you.