Don't get exctied about taking Lithium. It is not just a salt. It has side effects. I have taken it in the past. My relative, who is a doctor, heard about me taking it and told me to stop, that it could cause long term damage.
I know Depression is really hard to deal with. Just do some research on the side effects before taking anything. I was diagnosed with Candida 20 years ago. I've had continued Candida for over 20 years (because I didn't understand the disease or how to treat it) so I know all about depression. I have taken most every drug available for it over the years. Now I am paying the price, with a toxic everything in my body.
Studies have shown that exercise is the best thing for depression. For those of you who can exercise (I can't. I'm too weak.) that is the best thing.
There is also such joy that comes about by having a relationship with God. That will beat the Depression by itself.