Lithium Side Effects

I recently added Lithium Carbonate to my SSRI. I have Bipolar 2 with Major Depressive Disorder and a bunch of anxiety and CPTSD stuff.

So far, since starting Lithium a month ago, I really notice a positive improvement in my mood and also my stability. I'm only on a low dose of Lithium (300 mg. I started at 150 mg and I've been at 300 mg for about 2 weeks). I'm kind of blown away by the fact that this actually seems to be working for me so far. I was incredibly anxious about starting Lithium because it's notorious for causing side effects and actual kidney/thyroid damage if it's taken long term. Obviously I'm getting tested regularly.

Even at this low dose I'm having some unpleasant side effects, mostly to do with my digestive system, but also a really dry mouth, dry eyes and a scratchy throat. I take the Lithium with food and the nausea has got a bit better. But I still get bad indigestion (heartburn and reflux mainly). Does this get better? Did anyone else get the dry mouth/eyes/throat? Does that wear off?

I really want to stay on this medication, and ideally, I'd like to increase my dose a bit, but these side effects are bothersome and I don't want them to get worse.

Thank you!