We've tried Omnicef and Cefzil and both gave diahrea and he had a horrible rash on his bottom. So after the 1st injection he went the next day for a recheck, and he gave him another injection of Rocephin 250mg. I just read on the warning that you should wait 48 hours in between injections. Is this okay? What should I look for if there is any side effects? Thanks.