Halted back mri twice - back spasmed too uch. GP gave me Xanax but said the lithium I take made him not want to Rx anything for the back pain. I also take risporil and am 42, and had a cervical discsurgery ten years ago. Can I not Take gabapentin, Fentanyl or something for my back with lithium? If so, will a couple days without lithium help? Seems like my doc is not understanding me.