Is it possible to get dehydrated from augmentin antibiotics? I have been very thirsty, dry mouth, dry skin, diarrhea, just vomited, little urine output, and no fever, but have been extremely tired. I had a double ear infection and bad sinus infection a week ago, which is when I started the augmentin. I was on keflex 3 weeks ago for double ear infection and sinus infection.