I was wondering how common serum sickness is in children. DS was hospitalized after given Augmentin in Dec '10 due to what his pulmo says is serum sickness. However, his allergist had him try Augmentin again, saying that it was probably just a virus causing the swelling, etc. Sure enough, a week into the Augmentin and he developed hives, just as he did the 1st time. Now his allergist wants him to try taking Augmentin again, because he says serum sickness is so uncommon. Firing allergist, I'm not putting DS through this again or risking a more severe reaction. His symptoms were classic for serum sickness! Just curious as to how many others developed serum sickness to an antibiotic. I understand it is uncommon and the risks increase with antibiotic usage, but my daughter was on lots of antibiotics when she was young due to reoccurring strep, but never developed anything like this. I've had friends whose children were on constant antibiotics due to ear infections, later resulting in tubes, and this never happened. Is it more common in CF and if so does anyone know why?