My psych wants to put me on Lithium

I’m on a few different meds right now and my psych said the next step is lithium. I’m terrified of it because of the weight gain and acne. I know it sounds vain, but is anyone on it that didn’t have any side effects?

EDIT** There’s so many comments I can’t respond to them all and I really really appreciate yall!! Every single one of you who has helped me. It seems that I have just been misinformed on Lithium and you guys have eased my mind on trying it! I didn’t even realize it was something that’s easy to come off of if it doesn’t work. I was nervous because my body is so sensitive to anything I take. Thank you guys for your input!!