My son is 15 months. He has been on Omnicef 2 times prior to this...

My son is 15 months. He has been on Omnicef 2 times prior to this with only great results. Where other drugs had failed to cure his infections, omnicef wiped it out. Yet this time I have a different story. I am an RN and have enough education to know that the problem may not be omnicef at all but yeasterday I swore I knew it was. Four days ago my son begain running a temp (102/103). I don't like to rush to antibiotics everytime he gets sick so I decided to wait a while to see what happens (because this was really the only symptom he had). After about a day and a half I noticed a little sinus drainage. My sister in law who is a Family Nurse Practitioner took a look at him and said he has a bit of an ear infection and inflammed throat so she decided to put him on omnicef. The next day his fever broke and seemed to be feeling better. Of course I noticed the usual reddish colored stools but this is normal (as well as some abdominal discomfort and runny stools). Anyways after about 3 doses of omnicef he began to develop a rash on his trunk. This same rash had appeared the last time he had augmentin and thus his Drs weren't sure if he was allergic or not. The rash isn't hives or the type of rash associated with allergies so it was a bit confusing. But, after his 4th dose the rash got 10 times worse. Naturally I started to freak out but this morning I took him to his pediatrician and he thinks its roseola. After reading more about Roseola I am fairly certain this is it but I'm still quite confused about the coincidence with this rash appearing after augmentin and now omnicef. I know that there is cross-sensitivity between penecillins (augmentin) and cephlasporins (omnicef) and so I was really convinced he was having some sort of mild allergic reaction to both. After educating myself more on the signs and symptoms of roseola, I am 99% sure that it is the real culpret. I do wonder however if antibiotics such as the ones I mentioned can aggrivate it??? Anyone else out there have any similar experiences??? By the way, because I am a mother and a nurse, I find it hard to discredit other parents beliefs when it comes to things like this, but you must always stop and ask yourselves if some of these strange "behaviors" aren't due to the fact that your kids are already ill? My son kept me up all night long too and I admit it is tempting to blame the drug but who really knows. My advice is to take the severity of the situation into strong consideration. Like I said, I have had wonderful results with omnicef in the past. but just because a drug works, doesn't mean it doesn't have consequences. Its when the risks outwiegh the benefits that another option should be sought after.