Hi KeepingThe Faith,
I'm sorry I am not familiar with either of these meds. I'm sure someone who is will be along shortly to help out.
Have you been on the Lithium long? Is it possible that your body will adjust to it in time or maybe your doc has you on too high a dose?
In the meantime, stay safe, try and do some gentle movement, even if it's just to the letterbox, and hang in there.