Hello, my son is 3 1/2 years old and has been on Cefdinir for a few days for an ongoing "sinus infection", diagnosed by the Pediatrician. He is also currently on Prednisone and Pepcid to treat Nephrotic Syndrome, which is a kidney syndrome. the past couple of days i have noticed a severe pimply rash in between his butt cheeks, he has had a lot of diarrahea, which is a side affect of Cefdinr. He says it doesnt hurt or itch but it looks very painful. Any suggestions would be very apprecitated. I have given him oatmeal baths as well as put Desitin on. Please help