upper respiratory tract infection
"Was prescribed Bactrim for a UTI . Within minutes of taking my first dose I became extremely itchy and developed welts... 
I stopped taking it and it took two days for the itch to calm down. 
So apparently I'm allergic to it. Had to get a different drug called in which was CIPRO will not take that one do to bad side effects so now I'm on Macrobid. Will see how this goes."