skin or soft tissue infection
"Got 500mg of Keflex prescribed to me for alleged infected spider bites. Day one I felt ok, had to go to the bathroom a lot but otherwise my stomach wasn't too bad. By Night two I was on the verge of going to the ER. My stomach felt like it was eating itself, my BP/pulse through the roof, every muscle in my body was spasming and I was in full freak out mode. Stopped taking it after that. It's been four days since I took it and I'm still sick. Dizzy, can't eat, feel crappy and weak. Doc said the antibiotics made me sick and that I had to be on the BRAT  diet (bananas, rice, applesauce, and toast) for a week. FUN!"