bacterial infection
"I had a dog bites and was taking Bactrim for 6 days.  Not helping.  My Dr. Prescribed Amox-Clav. Augmentin.  Same day started bloody diarrhea.  Kept for the whole 5 days I was taking it, till I stopped.  Lost 10 pounds, dehydrated, and got severe lower back pains from the dehydration.  My doctor told me to stop immediately.  He also said after that much Diarrhea, I should go to the store and get over the counter PROBIOTICS to replace the good bacteria in my stomach. He said to take that for a week or two."