I just recently finished a fairly long course of Bactrim for a staph infection, possible MRSA. I felt pretty crappy overall on that med- not my UC, just bad in general! Shaky, edgy, headachy, spacey, dizzy... you name it. Apparently, those types of side effects are pretty common for Bactrim, quite a few people have bad enough side effects to quit the med. Probiotics will help if she's having bowel problems from the Bactrim, but for the other complaints, it's either deal with them & be sort of miserable, or switch to another antibiotic. And definitely try to touch base with her doctor.